diff --git a/bigdecimal.gemspec b/bigdecimal.gemspec
index 2b1ff6a6..fd49c1b0 100644
--- a/bigdecimal.gemspec
+++ b/bigdecimal.gemspec
@@ -2,7 +2,7 @@
 
 Gem::Specification.new do |s|
   s.name          = "bigdecimal"
-  s.version       = "3.1.0"
+  s.version       = "3.1.1"
   s.authors       = ["Kenta Murata", "Zachary Scott", "Shigeo Kobayashi"]
   s.email         = ["mrkn@mrkn.jp"]