diff --git a/apache/rocketmq/v2/definition.proto b/apache/rocketmq/v2/definition.proto
index 2513bac..6be0c05 100644
--- a/apache/rocketmq/v2/definition.proto
+++ b/apache/rocketmq/v2/definition.proto
@@ -149,6 +149,9 @@ enum MessageType {
 
   // lite topic
   LITE = 5;
+
+  // Messages that lower prioritised ones may need to wait for higher priority messages to be processed first
+  PRIORITY = 6;
 }
 
 enum DigestType {
@@ -278,6 +281,9 @@ message SystemProperties {
 
   // lite topic
   optional string lite_topic = 21;
+
+  // Priority of message, which is optional
+  optional int32 priority = 22;
 }
 
 message DeadLetterQueue {