diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst
index 1dc3282..0303152 100644
--- a/doc/guides/nics/mlx5.rst
+++ b/doc/guides/nics/mlx5.rst
@@ -54,6 +54,7 @@ Features
 - Support for scattered TX and RX frames.
 - IPv4, IPv6, TCPv4, TCPv6, UDPv4 and UDPv6 RSS on any number of queues.
 - Several RSS hash keys, one for each flow type.
+- Default RSS operation with no hash key specification.
 - Configurable RETA table.
 - Support for multiple MAC addresses.
 - VLAN filtering.
diff --git a/drivers/net/mlx5/mlx5_flow.c b/drivers/net/mlx5/mlx5_flow.c
index 107a4f0..677d2c4 100644
--- a/drivers/net/mlx5/mlx5_flow.c
+++ b/drivers/net/mlx5/mlx5_flow.c
@@ -912,12 +912,12 @@ uint32_t mlx5_flow_adjust_priority(struct rte_eth_dev *dev, int32_t priority,
 					  RTE_FLOW_ERROR_TYPE_ACTION_CONF,
 					  &rss->level,
 					  "tunnel RSS is not supported");
-	if (rss->key_len < MLX5_RSS_HASH_KEY_LEN)
+	if (rss->key && rss->key_len < MLX5_RSS_HASH_KEY_LEN)
 		return rte_flow_error_set(error, ENOTSUP,
 					  RTE_FLOW_ERROR_TYPE_ACTION_CONF,
 					  &rss->key_len,
 					  "RSS hash key too small");
-	if (rss->key_len > MLX5_RSS_HASH_KEY_LEN)
+	if (rss->key && rss->key_len > MLX5_RSS_HASH_KEY_LEN)
 		return rte_flow_error_set(error, ENOTSUP,
 					  RTE_FLOW_ERROR_TYPE_ACTION_CONF,
 					  &rss->key_len,
diff --git a/drivers/net/mlx5/mlx5_flow_dv.c b/drivers/net/mlx5/mlx5_flow_dv.c
index c11ecd4..cdf3377 100644
--- a/drivers/net/mlx5/mlx5_flow_dv.c
+++ b/drivers/net/mlx5/mlx5_flow_dv.c
@@ -1758,8 +1758,11 @@
 			memcpy((*flow->queue), rss->queue,
 			       rss->queue_num * sizeof(uint16_t));
 		flow->rss.queue_num = rss->queue_num;
-		memcpy(flow->key, rss->key, MLX5_RSS_HASH_KEY_LEN);
-		flow->rss.types = rss->types;
+		/* NULL RSS key indicates default RSS key. */
+		rss_key = !rss->key ? rss_hash_default_key : rss->key;
+		memcpy(flow->key, rss_key, MLX5_RSS_HASH_KEY_LEN);
+		/* RSS type 0 indicates default RSS type ETH_RSS_IP. */
+		flow->rss.types = !rss->types ? ETH_RSS_IP : rss->types;
 		flow->rss.level = rss->level;
 		/* Added to array only in apply since we need the QP */
 		flow->actions |= MLX5_FLOW_ACTION_RSS;
diff --git a/drivers/net/mlx5/mlx5_flow_verbs.c b/drivers/net/mlx5/mlx5_flow_verbs.c
index 2e506b9..54ac620 100644
--- a/drivers/net/mlx5/mlx5_flow_verbs.c
+++ b/drivers/net/mlx5/mlx5_flow_verbs.c
@@ -925,14 +925,18 @@
 				struct mlx5_flow *dev_flow)
 {
 	const struct rte_flow_action_rss *rss = action->conf;
+	const uint8_t *rss_key;
 	struct rte_flow *flow = dev_flow->flow;
 
 	if (flow->queue)
 		memcpy((*flow->queue), rss->queue,
 		       rss->queue_num * sizeof(uint16_t));
 	flow->rss.queue_num = rss->queue_num;
-	memcpy(flow->key, rss->key, MLX5_RSS_HASH_KEY_LEN);
-	flow->rss.types = rss->types;
+	/* NULL RSS key indicates default RSS key. */
+	rss_key = !rss->key ? rss_hash_default_key : rss->key;
+	memcpy(flow->key, rss_key, MLX5_RSS_HASH_KEY_LEN);
+	/* RSS type 0 indicates default RSS type (ETH_RSS_IP). */
+	flow->rss.types = !rss->types ? ETH_RSS_IP : rss->types;
 	flow->rss.level = rss->level;
 	*action_flags |= MLX5_FLOW_ACTION_RSS;
 }
diff --git a/drivers/net/mlx5/mlx5_rxq.c b/drivers/net/mlx5/mlx5_rxq.c
index 6df8997..eef4850 100644
--- a/drivers/net/mlx5/mlx5_rxq.c
+++ b/drivers/net/mlx5/mlx5_rxq.c
@@ -1794,10 +1794,6 @@ struct mlx5_hrxq *
 		rte_errno = ENOMEM;
 		return NULL;
 	}
-	if (!rss_key_len) {
-		rss_key_len = MLX5_RSS_HASH_KEY_LEN;
-		rss_key = rss_hash_default_key;
-	}
 #ifdef HAVE_IBV_DEVICE_TUNNEL_SUPPORT
 	if (tunnel) {
 		qp_init_attr.comp_mask =
@@ -1823,11 +1819,8 @@ struct mlx5_hrxq *
 				IBV_QP_INIT_ATTR_RX_HASH,
 			.rx_hash_conf = (struct ibv_rx_hash_conf){
 				.rx_hash_function = IBV_RX_HASH_FUNC_TOEPLITZ,
-				.rx_hash_key_len = rss_key_len ? rss_key_len :
-						   MLX5_RSS_HASH_KEY_LEN,
-				.rx_hash_key = rss_key ?
-					       (void *)(uintptr_t)rss_key :
-					       rss_hash_default_key,
+				.rx_hash_key_len = rss_key_len,
+				.rx_hash_key = (void *)(uintptr_t)rss_key,
 				.rx_hash_fields_mask = hash_fields,
 			},
 			.rwq_ind_tbl = ind_tbl->ind_table,
@@ -1845,11 +1838,8 @@ struct mlx5_hrxq *
 				IBV_QP_INIT_ATTR_RX_HASH,
 			.rx_hash_conf = (struct ibv_rx_hash_conf){
 				.rx_hash_function = IBV_RX_HASH_FUNC_TOEPLITZ,
-				.rx_hash_key_len = rss_key_len ? rss_key_len :
-						   MLX5_RSS_HASH_KEY_LEN,
-				.rx_hash_key = rss_key ?
-					       (void *)(uintptr_t)rss_key :
-					       rss_hash_default_key,
+				.rx_hash_key_len = rss_key_len,
+				.rx_hash_key = (void *)(uintptr_t)rss_key,
 				.rx_hash_fields_mask = hash_fields,
 			},
 			.rwq_ind_tbl = ind_tbl->ind_table,
