diff --git a/build.gradle b/build.gradle
index 1d2c4d58bf..d59037ec34 100644
--- a/build.gradle
+++ b/build.gradle
@@ -12,7 +12,7 @@ apply plugin: 'maven'
 
 allprojects {
     group = 'io.digdag'
-    version = '0.9.40-SNAPSHOT'
+    version = '0.9.40'
 
     ext {
         isSnapshotRelease = version.endsWith('-SNAPSHOT')
diff --git a/digdag-cli/src/main/java/io/digdag/cli/SelfUpdate.java b/digdag-cli/src/main/java/io/digdag/cli/SelfUpdate.java
index 81a5e09831..69a8410c0a 100644
--- a/digdag-cli/src/main/java/io/digdag/cli/SelfUpdate.java
+++ b/digdag-cli/src/main/java/io/digdag/cli/SelfUpdate.java
@@ -90,7 +90,7 @@ public SystemExitException usage(String error)
         err.println("");
         err.println("  Examples:");
         err.println("    $ " + programName + " selfupdate");
-        err.println("    $ " + programName + " selfupdate 0.9.40-SNAPSHOT");
+        err.println("    $ " + programName + " selfupdate 0.9.40");
         err.println("");
         return systemExit(error);
     }
diff --git a/digdag-client/src/main/resources/io/digdag/client/version.txt b/digdag-client/src/main/resources/io/digdag/client/version.txt
index db8ee74f7b..f81283f3b1 100644
--- a/digdag-client/src/main/resources/io/digdag/client/version.txt
+++ b/digdag-client/src/main/resources/io/digdag/client/version.txt
@@ -1 +1 @@
-0.9.40-SNAPSHOT
+0.9.40
diff --git a/digdag-docs/src/command_reference.rst b/digdag-docs/src/command_reference.rst
index 14a57acf7d..f91006bc82 100644
--- a/digdag-docs/src/command_reference.rst
+++ b/digdag-docs/src/command_reference.rst
@@ -241,7 +241,7 @@ Updates the executable binary file to the latest version or specified version. E
 .. code-block:: console
 
     $ digdag selfupdate
-    $ digdag selfupdate 0.9.39
+    $ digdag selfupdate 0.9.40
 
 Server-mode commands
 ----------------------------------
diff --git a/digdag-docs/src/releases.rst b/digdag-docs/src/releases.rst
index e7a5e3b388..a73508fc84 100644
--- a/digdag-docs/src/releases.rst
+++ b/digdag-docs/src/releases.rst
@@ -5,6 +5,7 @@ Release Notes
     :maxdepth: 1
 
     # add new version here
+    releases/release-0.9.40
     releases/release-0.9.39
     releases/release-0.9.38
     releases/release-0.9.37
diff --git a/digdag-docs/src/releases/release-0.9.40.rst b/digdag-docs/src/releases/release-0.9.40.rst
new file mode 100644
index 0000000000..d27429520a
--- /dev/null
+++ b/digdag-docs/src/releases/release-0.9.40.rst
@@ -0,0 +1,49 @@
+Release 0.9.40
+==============
+
+General Changes
+---------------
+
+* Improve performance of project list API. [#1187]
+* Task log is split by size in configuration. [#1209]
+* Output of echo> operator is stored to task log. [#1221]
+* Upgrade Guice. [#791]
+* Document improvements. [#1144 #1181 #1201 #1218 #1236 #1273]
+
+
+Fixed Issues
+------------
+* Fix BigQuery operators parameter name. [#1225]
+* Fix migration command issue. [#1248]
+* CLI related improvements. [#1257 #1250]
+* UI packages update. [#1185 #1186 #1214]
+* CI related improvements. [#1230 #1255]
+
+Release Date
+------------
+2019-12-11
+
+Contributors
+------------
+* Aki Ariga
+* Edd Steel
+* Hiroyuki Sato
+* John Yani
+* Kohki Sato
+* Muga Nishizawa
+* NARUSE, Yui
+* NomadBlacky
+* Pierre Delagrave
+* Sadayuki Furuhashi
+* Satoru Kamikaseda
+* Shota Suzuki
+* Timothée Peignier
+* Weiming-Zhu
+* Y.Kentaro
+* katsuyan
+* makoto.toriyama
+* morihaya
+* rubyu
+* yui-knk
+* zaimy
+* yoyama