diff --git a/Casks/thunderbird-ja.rb b/Casks/thunderbird-ja.rb
index 026525fcc..097b0e664 100644
--- a/Casks/thunderbird-ja.rb
+++ b/Casks/thunderbird-ja.rb
@@ -1,6 +1,6 @@
 cask 'thunderbird-ja' do
-  version '45.2.0'
-  sha256 '9d93b199bc4da73b651975d880492cc1b77289017f3968e070dcb57ca0366837'
+  version '45.3.0'
+  sha256 '0b7b46c00d56abcff68f6b8bbc89c40f267c2163c79f48e9fb01db2eedb840d4'
 
   # mozilla.org was verified as official when first introduced to the cask
   url "https://download.mozilla.org/?product=thunderbird-#{version}&os=osx&lang=ja-JP-mac"