diff --git a/README.md b/README.md
index 547a9a291..cbf4aa12e 100755
--- a/README.md
+++ b/README.md
@@ -159,6 +159,7 @@ For previous versions, please read:
 
 ## V4 changes
 
+* v4.0, 2020-08-30, Fix serval bugs for RTC. Refine context API. 4.0.40
 * v4.0, 2020-08-18, RTC: DTLS support ARQ, covered with utest. 4.0.39
 * v4.0, 2020-08-06, RTC: Refine error check. 4.0.37
 * v4.0, 2020-07-25, RTC: Support multiple address for client. 4.0.36
diff --git a/trunk/src/core/srs_core_version4.hpp b/trunk/src/core/srs_core_version4.hpp
index bdc884573..566ca6ed1 100644
--- a/trunk/src/core/srs_core_version4.hpp
+++ b/trunk/src/core/srs_core_version4.hpp
@@ -24,6 +24,6 @@
 #ifndef SRS_CORE_VERSION4_HPP
 #define SRS_CORE_VERSION4_HPP
 
-#define SRS_VERSION4_REVISION 39
+#define SRS_VERSION4_REVISION 40
 
 #endif