diff --git a/src/socks5.h b/src/socks5.h
index cc9ed4b9..42dbcfe2 100644
--- a/src/socks5.h
+++ b/src/socks5.h
@@ -30,7 +30,7 @@
 // see also: https://www.ietf.org/rfc/rfc1928.txt
 #define SOCKS5_CMD_CONNECT 0x01
 #define SOCKS5_CMD_BIND 0x02
-#define SOCKS5_CMD_UDP_ASSOCIATE 0x02
+#define SOCKS5_CMD_UDP_ASSOCIATE 0x03
 
 #define SOCKS5_ATYP_IPV4 0x01
 #define SOCKS5_ATYP_DOMAIN 0x03