diff --git a/src/protocol.cpp b/src/protocol.cpp
index c1c7c0b96bf..1ddb65b7968 100644
--- a/src/protocol.cpp
+++ b/src/protocol.cpp
@@ -28,7 +28,6 @@ const char *GETADDR="getaddr";
 const char *MEMPOOL="mempool";
 const char *PING="ping";
 const char *PONG="pong";
-const char *ALERT="alert";
 const char *NOTFOUND="notfound";
 const char *FILTERLOAD="filterload";
 const char *FILTERADD="filteradd";
@@ -64,7 +63,6 @@ const static std::string allNetMessageTypes[] = {
     NetMsgType::MEMPOOL,
     NetMsgType::PING,
     NetMsgType::PONG,
-    NetMsgType::ALERT,
     NetMsgType::NOTFOUND,
     NetMsgType::FILTERLOAD,
     NetMsgType::FILTERADD,
diff --git a/src/protocol.h b/src/protocol.h
index c8b8d20eadd..5504f213f47 100644
--- a/src/protocol.h
+++ b/src/protocol.h
@@ -163,13 +163,6 @@ extern const char *PING;
  * @see https://bitcoin.org/en/developer-reference#pong
  */
 extern const char *PONG;
-/**
- * The alert message warns nodes of problems that may affect them or the rest
- * of the network.
- * @since protocol version 311.
- * @see https://bitcoin.org/en/developer-reference#alert
- */
-extern const char *ALERT;
 /**
  * The notfound message is a reply to a getdata message which requested an
  * object the receiving node does not have available for relay.