diff --git a/northd/ovn-northd.c b/northd/ovn-northd.c
index 40aeb0a58..7887d0d2f 100644
--- a/northd/ovn-northd.c
+++ b/northd/ovn-northd.c
@@ -3121,6 +3121,7 @@ struct ovn_lb {
 
     const struct nbrec_load_balancer *nlb; /* May be NULL. */
     char *selection_fields;
+    char *proto;
     struct lb_vip *vips;
     size_t n_vips;
 };
@@ -3218,6 +3219,12 @@ ovn_lb_create(struct northd_context *ctx, struct hmap *lbs,
     struct smap_node *node;
     size_t n_vips = 0;
 
+    if (!nbrec_lb->protocol || !nbrec_lb->protocol[0]) {
+        lb->proto = xstrdup("tcp");
+    } else {
+        lb->proto = xstrdup(nbrec_lb->protocol);
+    }
+
     SMAP_FOR_EACH (node, &nbrec_lb->vips) {
         char *vip;
         uint16_t port;
@@ -3234,7 +3241,7 @@ ovn_lb_create(struct northd_context *ctx, struct hmap *lbs,
         lb->vips[n_vips].backend_ips = xstrdup(node->value);
 
         struct nbrec_load_balancer_health_check *lb_health_check = NULL;
-        if (nbrec_lb->protocol && !strcmp(nbrec_lb->protocol, "sctp")) {
+        if (!strcmp(lb->proto, "sctp")) {
             if (nbrec_lb->n_health_check > 0) {
                 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
                 VLOG_WARN_RL(&rl,
@@ -3309,15 +3316,11 @@ ovn_lb_create(struct northd_context *ctx, struct hmap *lbs,
             lb->vips[n_vips].backends[i].svc_mon_src_ip = svc_mon_src_ip;
 
             if (lb_health_check && op && svc_mon_src_ip) {
-                const char *protocol = nbrec_lb->protocol;
-                if (!protocol || !protocol[0]) {
-                    protocol = "tcp";
-                }
                 lb->vips[n_vips].backends[i].health_check = true;
                 struct service_monitor_info *mon_info =
                     create_or_get_service_mon(ctx, monitor_map, backend_ip,
                                               op->nbsp->name, backend_port,
-                                              protocol);
+                                              lb->proto);
 
                 ovs_assert(mon_info);
                 sbrec_service_monitor_set_options(
@@ -3351,7 +3354,14 @@ ovn_lb_create(struct northd_context *ctx, struct hmap *lbs,
     if (lb->nlb->n_selection_fields) {
         struct ds sel_fields = DS_EMPTY_INITIALIZER;
         for (size_t i = 0; i < lb->nlb->n_selection_fields; i++) {
-            ds_put_format(&sel_fields, "%s,", lb->nlb->selection_fields[i]);
+            char *field = lb->nlb->selection_fields[i];
+            if (!strcmp(field, "tp_src")) {
+                ds_put_format(&sel_fields, "%s_src,", lb->proto);
+            } else if (!strcmp(field, "tp_dst")) {
+                ds_put_format(&sel_fields, "%s_dst,", lb->proto);
+            } else {
+                ds_put_format(&sel_fields, "%s,", field);
+            }
         }
         ds_chomp(&sel_fields, ',');
         lb->selection_fields = ds_steal_cstr(&sel_fields);
@@ -3374,6 +3384,7 @@ ovn_lb_destroy(struct ovn_lb *lb)
 
         free(lb->vips[i].backends);
     }
+    free(lb->proto);
     free(lb->vips);
     free(lb->selection_fields);
 }
@@ -4820,7 +4831,7 @@ ls_has_dns_records(const struct nbrec_logical_switch *nbs)
 
 static void
 build_empty_lb_event_flow(struct ovn_datapath *od, struct hmap *lflows,
-                          struct lb_vip *lb_vip,
+                          struct lb_vip *lb_vip, const char *proto,
                           struct nbrec_load_balancer *lb,
                           int pl, struct shash *meter_groups)
 {
@@ -4837,11 +4848,11 @@ build_empty_lb_event_flow(struct ovn_datapath *od, struct hmap *lflows,
 
     ds_put_format(&match, "ip%s.dst == %s && %s",
                   lb_vip->addr_family == AF_INET ? "4": "6",
-                  lb_vip->vip, lb->protocol);
+                  lb_vip->vip, proto);
 
     char *vip = lb_vip->vip;
     if (lb_vip->vip_port) {
-        ds_put_format(&match, " && %s.dst == %u", lb->protocol,
+        ds_put_format(&match, " && %s.dst == %u", proto,
                       lb_vip->vip_port);
         vip = xasprintf("%s:%u", lb_vip->vip, lb_vip->vip_port);
     }
@@ -4851,7 +4862,7 @@ build_empty_lb_event_flow(struct ovn_datapath *od, struct hmap *lflows,
                        "protocol = \"%s\", "
                        "load_balancer = \"" UUID_FMT "\");",
                        event_to_string(OVN_EVENT_EMPTY_LB_BACKENDS),
-                       meter, vip, lb->protocol,
+                       meter, vip, proto,
                        UUID_ARGS(&lb->header_.uuid));
     ovn_lflow_add_with_hint(lflows, od, pl, 130, ds_cstr(&match), action,
                             &lb->header_);
@@ -4906,7 +4917,7 @@ build_pre_lb(struct ovn_datapath *od, struct hmap *lflows,
                 sset_add(&all_ips_v6, lb_vip->vip);
             }
 
-            build_empty_lb_event_flow(od, lflows, lb_vip, nb_lb,
+            build_empty_lb_event_flow(od, lflows, lb_vip, lb->proto, nb_lb,
                                       S_SWITCH_IN_PRE_LB, meter_groups);
 
             /* Ignore L4 port information in the key because fragmented packets
@@ -5577,7 +5588,7 @@ build_lb(struct ovn_datapath *od, struct hmap *lflows)
 static void
 build_lb_hairpin_rules(struct ovn_datapath *od, struct hmap *lflows,
                        struct ovn_lb *lb, struct lb_vip *lb_vip,
-                       const char *ip_match, const char *proto)
+                       const char *ip_match)
 {
     if (lb_vip->n_backends == 0) {
         return;
@@ -5605,7 +5616,7 @@ build_lb_hairpin_rules(struct ovn_datapath *od, struct hmap *lflows,
          */
         if (lb_vip->vip_port) {
             ds_put_format(&proto_match, " && %s.dst == %"PRIu16,
-                          proto, backend->port);
+                          lb->proto, backend->port);
         }
         ds_put_format(&match_initiator, "(%s.src == %s && %s.dst == %s%s)",
                       ip_match, backend->ip, ip_match, backend->ip,
@@ -5614,7 +5625,7 @@ build_lb_hairpin_rules(struct ovn_datapath *od, struct hmap *lflows,
         /* Replies to hairpinned traffic are originated by backend->ip:port. */
         ds_clear(&proto_match);
         if (lb_vip->vip_port) {
-            ds_put_format(&proto_match, " && %s.src == %"PRIu16, proto,
+            ds_put_format(&proto_match, " && %s.src == %"PRIu16, lb->proto,
                           backend->port);
         }
         ds_put_format(&match_reply, "(%s.src == %s%s)", ip_match, backend->ip,
@@ -5665,18 +5676,6 @@ build_lb_rules(struct ovn_datapath *od, struct hmap *lflows, struct ovn_lb *lb)
             ip_match = "ip6";
         }
 
-        const char *proto = NULL;
-        if (lb_vip->vip_port) {
-            proto = "tcp";
-            if (lb->nlb->protocol) {
-                if (!strcmp(lb->nlb->protocol, "udp")) {
-                    proto = "udp";
-                } else if (!strcmp(lb->nlb->protocol, "sctp")) {
-                    proto = "sctp";
-                }
-            }
-        }
-
         /* New connections in Ingress table. */
         struct ds action = DS_EMPTY_INITIALIZER;
         build_lb_vip_ct_lb_actions(lb_vip, &action, lb->selection_fields);
@@ -5684,7 +5683,8 @@ build_lb_rules(struct ovn_datapath *od, struct hmap *lflows, struct ovn_lb *lb)
         struct ds match = DS_EMPTY_INITIALIZER;
         ds_put_format(&match, "ct.new && %s.dst == %s", ip_match, lb_vip->vip);
         if (lb_vip->vip_port) {
-            ds_put_format(&match, " && %s.dst == %d", proto, lb_vip->vip_port);
+            ds_put_format(&match, " && %s.dst == %d", lb->proto,
+                          lb_vip->vip_port);
             ovn_lflow_add_with_hint(lflows, od, S_SWITCH_IN_STATEFUL, 120,
                                     ds_cstr(&match), ds_cstr(&action),
                                     &lb->nlb->header_);
@@ -5701,7 +5701,7 @@ build_lb_rules(struct ovn_datapath *od, struct hmap *lflows, struct ovn_lb *lb)
          * a load balancer VIP is DNAT-ed to a backend that happens to be
          * the source of the traffic).
          */
-        build_lb_hairpin_rules(od, lflows, lb, lb_vip, ip_match, proto);
+        build_lb_hairpin_rules(od, lflows, lb, lb_vip, ip_match);
     }
 }
 
@@ -7667,7 +7667,7 @@ add_router_lb_flow(struct hmap *lflows, struct ovn_datapath *od,
                    const char *proto, struct nbrec_load_balancer *lb,
                    struct shash *meter_groups, struct sset *nat_entries)
 {
-    build_empty_lb_event_flow(od, lflows, lb_vip, lb, S_ROUTER_IN_DNAT,
+    build_empty_lb_event_flow(od, lflows, lb_vip, proto, lb, S_ROUTER_IN_DNAT,
                               meter_groups);
 
     /* A match and actions for new connections. */
@@ -9358,14 +9358,9 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports,
                 }
 
                 int prio = 110;
-                bool is_udp = nullable_string_is_equal(nb_lb->protocol, "udp");
-                bool is_sctp = nullable_string_is_equal(nb_lb->protocol,
-                                                        "sctp");
-                const char *proto = is_udp ? "udp" : is_sctp ? "sctp" : "tcp";
-
                 if (lb_vip->vip_port) {
-                    ds_put_format(&match, " && %s && %s.dst == %d", proto,
-                                  proto, lb_vip->vip_port);
+                    ds_put_format(&match, " && %s && %s.dst == %d", lb->proto,
+                                  lb->proto, lb_vip->vip_port);
                     prio = 120;
                 }
 
@@ -9374,7 +9369,7 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports,
                                   od->l3redirect_port->json_key);
                 }
                 add_router_lb_flow(lflows, od, &match, &actions, prio,
-                                   lb_force_snat_ip, lb_vip, proto,
+                                   lb_force_snat_ip, lb_vip, lb->proto,
                                    nb_lb, meter_groups, &nat_entries);
             }
         }
diff --git a/tests/ovn.at b/tests/ovn.at
index 8ee348397..a28563a5e 100644
--- a/tests/ovn.at
+++ b/tests/ovn.at
@@ -1009,6 +1009,18 @@ ct_lb(backends=fd0f::2,fd0f::3; hash_fields="eth_src,eth_dst,ip_src,ip_dst,tp_sr
     encodes as group:5
     uses group: id(5), name(type=select,selection_method=hash,fields(eth_src,eth_dst,ip_src,ip_dst,tp_src,tp_dst),bucket=bucket_id=0,weight:100,actions=ct(nat(dst=fd0f::2),commit,table=19,zone=NXM_NX_REG13[0..15]),bucket=bucket_id=1,weight:100,actions=ct(nat(dst=fd0f::3),commit,table=19,zone=NXM_NX_REG13[0..15]))
     has prereqs ip
+ct_lb(backends=fd0f::2,fd0f::3; hash_fields="eth_src,eth_dst,ip_src,ip_dst,tcp_src,tcp_dst");
+    encodes as group:6
+    uses group: id(6), name(type=select,selection_method=hash,fields(eth_src,eth_dst,ip_src,ip_dst,tcp_src,tcp_dst),bucket=bucket_id=0,weight:100,actions=ct(nat(dst=fd0f::2),commit,table=19,zone=NXM_NX_REG13[0..15]),bucket=bucket_id=1,weight:100,actions=ct(nat(dst=fd0f::3),commit,table=19,zone=NXM_NX_REG13[0..15]))
+    has prereqs ip
+ct_lb(backends=fd0f::2,fd0f::3; hash_fields="eth_src,eth_dst,ip_src,ip_dst,udp_src,udp_dst");
+    encodes as group:7
+    uses group: id(7), name(type=select,selection_method=hash,fields(eth_src,eth_dst,ip_src,ip_dst,udp_src,udp_dst),bucket=bucket_id=0,weight:100,actions=ct(nat(dst=fd0f::2),commit,table=19,zone=NXM_NX_REG13[0..15]),bucket=bucket_id=1,weight:100,actions=ct(nat(dst=fd0f::3),commit,table=19,zone=NXM_NX_REG13[0..15]))
+    has prereqs ip
+ct_lb(backends=fd0f::2,fd0f::3; hash_fields="eth_src,eth_dst,ip_src,ip_dst,sctp_src,sctp_dst");
+    encodes as group:8
+    uses group: id(8), name(type=select,selection_method=hash,fields(eth_src,eth_dst,ip_src,ip_dst,sctp_src,sctp_dst),bucket=bucket_id=0,weight:100,actions=ct(nat(dst=fd0f::2),commit,table=19,zone=NXM_NX_REG13[0..15]),bucket=bucket_id=1,weight:100,actions=ct(nat(dst=fd0f::3),commit,table=19,zone=NXM_NX_REG13[0..15]))
+    has prereqs ip
 
 # ct_next
 ct_next;
@@ -1543,13 +1555,13 @@ handle_svc_check(reg0);
 # select
 reg9[16..31] = select(1=50, 2=100, 3, );
     formats as reg9[16..31] = select(1=50, 2=100, 3=100);
-    encodes as group:6
-    uses group: id(6), name(type=select,selection_method=dp_hash,bucket=bucket_id=0,weight:50,actions=load:1->xreg4[16..31],resubmit(,19),bucket=bucket_id=1,weight:100,actions=load:2->xreg4[16..31],resubmit(,19),bucket=bucket_id=2,weight:100,actions=load:3->xreg4[16..31],resubmit(,19))
+    encodes as group:9
+    uses group: id(9), name(type=select,selection_method=dp_hash,bucket=bucket_id=0,weight:50,actions=load:1->xreg4[16..31],resubmit(,19),bucket=bucket_id=1,weight:100,actions=load:2->xreg4[16..31],resubmit(,19),bucket=bucket_id=2,weight:100,actions=load:3->xreg4[16..31],resubmit(,19))
 
 reg0 = select(1, 2);
     formats as reg0 = select(1=100, 2=100);
-    encodes as group:7
-    uses group: id(7), name(type=select,selection_method=dp_hash,bucket=bucket_id=0,weight:100,actions=load:1->xxreg0[96..127],resubmit(,19),bucket=bucket_id=1,weight:100,actions=load:2->xxreg0[96..127],resubmit(,19))
+    encodes as group:10
+    uses group: id(10), name(type=select,selection_method=dp_hash,bucket=bucket_id=0,weight:100,actions=load:1->xxreg0[96..127],resubmit(,19),bucket=bucket_id=1,weight:100,actions=load:2->xxreg0[96..127],resubmit(,19))
 
 reg0 = select(1=, 2);
     Syntax error at `,' expecting weight.
@@ -1565,12 +1577,12 @@ reg0[0..14] = select(1, 2, 3);
     cannot use 15-bit field reg0[0..14] for "select", which requires at least 16 bits.
 
 fwd_group(liveness="true", childports="eth0", "lsp1");
-    encodes as group:8
-    uses group: id(8), name(type=select,selection_method=dp_hash,bucket=watch_port:5,load=0x5->NXM_NX_REG15[0..15],resubmit(,64),bucket=watch_port:17,load=0x17->NXM_NX_REG15[0..15],resubmit(,64))
+    encodes as group:11
+    uses group: id(11), name(type=select,selection_method=dp_hash,bucket=watch_port:5,load=0x5->NXM_NX_REG15[0..15],resubmit(,64),bucket=watch_port:17,load=0x17->NXM_NX_REG15[0..15],resubmit(,64))
 
 fwd_group(childports="eth0", "lsp1");
-    encodes as group:9
-    uses group: id(9), name(type=select,selection_method=dp_hash,bucket=load=0x5->NXM_NX_REG15[0..15],resubmit(,64),bucket=load=0x17->NXM_NX_REG15[0..15],resubmit(,64))
+    encodes as group:12
+    uses group: id(12), name(type=select,selection_method=dp_hash,bucket=load=0x5->NXM_NX_REG15[0..15],resubmit(,64),bucket=load=0x17->NXM_NX_REG15[0..15],resubmit(,64))
 
 fwd_group(childports=eth0);
     Syntax error at `eth0' expecting logical switch port.
@@ -19905,3 +19917,154 @@ OVS_WAIT_UNTIL([test 0 = $(ovn-sbctl show | grep Port_Binding -c)], [0])
 
 OVN_CLEANUP([hv1])
 AT_CLEANUP
+
+AT_SETUP([ovn -- Load balancer selection fields])
+AT_KEYWORDS([lb])
+ovn_start
+
+net_add n1
+
+sim_add hv1
+as hv1
+ovs-vsctl add-br br-phys
+ovn_attach n1 br-phys 192.168.0.1
+ovs-vsctl -- add-port br-int hv1-vif1 -- \
+    set interface hv1-vif1 external-ids:iface-id=sw0-p1 \
+    options:tx_pcap=hv1/vif1-tx.pcap \
+    options:rxq_pcap=hv1/vif1-rx.pcap \
+    ofport-request=1
+ovs-vsctl -- add-port br-int hv1-vif2 -- \
+    set interface hv1-vif2 external-ids:iface-id=sw0-p2 \
+    options:tx_pcap=hv1/vif2-tx.pcap \
+    options:rxq_pcap=hv1/vif2-rx.pcap \
+    ofport-request=2
+
+sim_add hv2
+as hv2
+ovs-vsctl add-br br-phys
+ovn_attach n1 br-phys 192.168.0.2
+ovs-vsctl -- add-port br-int hv2-vif1 -- \
+    set interface hv2-vif1 external-ids:iface-id=sw1-p1 \
+    options:tx_pcap=hv2/vif1-tx.pcap \
+    options:rxq_pcap=hv2/vif1-rx.pcap \
+    ofport-request=1
+
+ovn-nbctl ls-add sw0
+
+ovn-nbctl lsp-add sw0 sw0-p1
+ovn-nbctl lsp-set-addresses sw0-p1 "50:54:00:00:00:03 10.0.0.3"
+ovn-nbctl lsp-set-port-security sw0-p1 "50:54:00:00:00:03 10.0.0.3"
+
+ovn-nbctl lsp-add sw0 sw0-p2
+ovn-nbctl lsp-set-addresses sw0-p2 "50:54:00:00:00:04 10.0.0.4"
+ovn-nbctl lsp-set-port-security sw0-p2 "50:54:00:00:00:04 10.0.0.4"
+
+# Create port group and ACLs for sw0 ports.
+ovn-nbctl pg-add pg0_drop sw0-p1 sw0-p2
+ovn-nbctl acl-add pg0_drop from-lport 1001 "inport == @pg0_drop && ip" drop
+ovn-nbctl acl-add pg0_drop to-lport 1001 "outport == @pg0_drop && ip" drop
+
+ovn-nbctl pg-add pg0 sw0-p1 sw0-p2
+ovn-nbctl acl-add pg0 from-lport 1002 "inport == @pg0 && ip4" allow-related
+ovn-nbctl acl-add pg0 to-lport 1002 "outport == @pg0 && ip4 && ip4.src == 0.0.0.0/0 && icmp4" allow-related
+ovn-nbctl acl-add pg0 to-lport 1002 "outport == @pg0 && ip4 && ip4.src == 0.0.0.0/0 && tcp && tcp.dst == 80" allow-related
+ovn-nbctl acl-add pg0 to-lport 1002 "outport == @pg0 && ip4 && ip4.src == 0.0.0.0/0 && udp && udp.dst == 80" allow-related
+
+# Create the second logical switch with one port
+ovn-nbctl ls-add sw1
+ovn-nbctl lsp-add sw1 sw1-p1
+ovn-nbctl lsp-set-addresses sw1-p1 "40:54:00:00:00:03 20.0.0.3"
+ovn-nbctl lsp-set-port-security sw1-p1 "40:54:00:00:00:03 20.0.0.3"
+
+# Create port group and ACLs for sw1 ports.
+ovn-nbctl pg-add pg1_drop sw1-p1
+ovn-nbctl acl-add pg1_drop from-lport 1001 "inport == @pg1_drop && ip" drop
+ovn-nbctl acl-add pg1_drop to-lport 1001 "outport == @pg1_drop && ip" drop
+
+ovn-nbctl pg-add pg1 sw1-p1
+ovn-nbctl acl-add pg1 from-lport 1002 "inport == @pg1 && ip4" allow-related
+ovn-nbctl acl-add pg1 to-lport 1002 "outport == @pg1 && ip4 && ip4.src == 0.0.0.0/0 && icmp4" allow-related
+ovn-nbctl acl-add pg1 to-lport 1002 "outport == @pg1 && ip4 && ip4.src == 0.0.0.0/0 && tcp && tcp.dst == 80" allow-related
+ovn-nbctl acl-add pg1 to-lport 1002 "outport == @pg1 && ip4 && ip4.src == 0.0.0.0/0 && udp && udp.dst == 80" allow-related
+
+# Create a logical router and attach both logical switches
+ovn-nbctl lr-add lr0
+ovn-nbctl lrp-add lr0 lr0-sw0 00:00:00:00:ff:01 10.0.0.1/24
+ovn-nbctl lsp-add sw0 sw0-lr0
+ovn-nbctl lsp-set-type sw0-lr0 router
+ovn-nbctl lsp-set-addresses sw0-lr0 router
+ovn-nbctl lsp-set-options sw0-lr0 router-port=lr0-sw0
+
+ovn-nbctl lrp-add lr0 lr0-sw1 00:00:00:00:ff:02 20.0.0.1/24
+ovn-nbctl lsp-add sw1 sw1-lr0
+ovn-nbctl lsp-set-type sw1-lr0 router
+ovn-nbctl lsp-set-addresses sw1-lr0 router
+ovn-nbctl lsp-set-options sw1-lr0 router-port=lr0-sw1
+
+ovn-nbctl lb-add lb1 10.0.0.10:80 10.0.0.3:80,20.0.0.3:80
+lb1_uuid=$(ovn-nbctl --bare --columns _uuid list load_balancer)
+ovn-nbctl ls-lb-add sw0 lb1
+ovn-nbctl ls-lb-add sw1 lb1
+ovn-nbctl lr-lb-add lr0 lb1
+
+OVS_WAIT_UNTIL([
+    test $(as hv1 ovs-ofctl dump-groups br-int | \
+    grep "selection_method=dp_hash" -c) -eq 1
+])
+
+OVS_WAIT_UNTIL([
+    test $(as hv2 ovs-ofctl dump-groups br-int | \
+    grep "selection_method=dp_hash" -c) -eq 1
+])
+
+echo "lb1_uuid = $lb1_uuid"
+
+ovn-nbctl set load_balancer $lb1_uuid selection_fields="ip_src,ip_dst,tp_src,tp_dst"
+
+OVS_WAIT_UNTIL([
+    test $(as hv1 ovs-ofctl dump-groups br-int | \
+    grep "selection_method=hash,fields(ip_src,ip_dst,tcp_src,tcp_dst)" -c) -eq 1
+])
+
+OVS_WAIT_UNTIL([
+    test $(as hv2 ovs-ofctl dump-groups br-int | \
+    grep "selection_method=hash,fields(ip_src,ip_dst,tcp_src,tcp_dst)" -c) -eq 1
+])
+
+# Change the protocol to udp.
+ovn-nbctl set load_balancer $lb1_uuid protocol=udp
+OVS_WAIT_UNTIL([
+    test $(as hv1 ovs-ofctl dump-groups br-int | \
+    grep "selection_method=hash,fields(ip_src,ip_dst,udp_src,udp_dst)" -c) -eq 1
+])
+
+OVS_WAIT_UNTIL([
+    test $(as hv2 ovs-ofctl dump-groups br-int | \
+    grep "selection_method=hash,fields(ip_src,ip_dst,udp_src,udp_dst)" -c) -eq 1
+])
+
+# Change the protocol to udp.
+ovn-nbctl set load_balancer $lb1_uuid protocol=sctp
+OVS_WAIT_UNTIL([
+    test $(as hv1 ovs-ofctl dump-groups br-int | \
+    grep "selection_method=hash,fields(ip_src,ip_dst,sctp_src,sctp_dst)" -c) -eq 1
+])
+
+OVS_WAIT_UNTIL([
+    test $(as hv2 ovs-ofctl dump-groups br-int | \
+    grep "selection_method=hash,fields(ip_src,ip_dst,sctp_src,sctp_dst)" -c) -eq 1
+])
+
+ovn-nbctl set load_balancer $lb1_uuid selection_fields="ip_src,ip_dst,tp_dst"
+OVS_WAIT_UNTIL([
+    test $(as hv1 ovs-ofctl dump-groups br-int | \
+    grep "selection_method=hash,fields(ip_src,ip_dst,sctp_dst)" -c) -eq 1
+])
+
+OVS_WAIT_UNTIL([
+    test $(as hv2 ovs-ofctl dump-groups br-int | \
+    grep "selection_method=hash,fields(ip_src,ip_dst,sctp_dst)" -c) -eq 1
+])
+
+OVN_CLEANUP([hv1], [hv2])
+AT_CLEANUP
diff --git a/tests/system-ovn.at b/tests/system-ovn.at
index 52f05f07e..2999e52fd 100644
--- a/tests/system-ovn.at
+++ b/tests/system-ovn.at
@@ -1234,6 +1234,29 @@ else
     AT_CHECK([test $bar3_ct -eq 0])
 fi
 
+# Change the protocol of lb2 to udp and set tp_src and tp_dst.
+ovn-nbctl set load_balancer $lb2_uuid selection_fields="ip_src,ip_dst,tp_src,tp_dst"
+
+OVS_WAIT_UNTIL([
+    test $(ovs-ofctl dump-groups br-int | \
+    grep "selection_method=hash,fields(ip_src,ip_dst,tcp_src,tcp_dst)" -c) -eq 2
+])
+
+ovn-nbctl set load_balancer $lb2_uuid protocol=udp
+
+OVS_WAIT_UNTIL([
+    test $(ovs-ofctl dump-groups br-int | \
+    grep "selection_method=hash,fields(ip_src,ip_dst,udp_src,udp_dst)" -c) -eq 2
+])
+
+# Change the protocol of lb2 to sctp.
+ovn-nbctl set load_balancer $lb2_uuid protocol=sctp
+
+OVS_WAIT_UNTIL([
+    test $(ovs-ofctl dump-groups br-int | \
+    grep "selection_method=hash,fields(ip_src,ip_dst,sctp_src,sctp_dst)" -c) -eq 2
+])
+
 OVS_APP_EXIT_AND_WAIT([ovn-controller])
 
 as ovn-sb
