diff --git a/Gemfile.lock b/Gemfile.lock
index adf964b..e429cb4 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -8,9 +8,10 @@ GEM
   specs:
     diff-lcs (1.3)
     minitest (5.11.3)
-    rake (10.5.0)
+    rake (13.0.1)
 
 PLATFORMS
+  ruby
   x64-mingw32
   x86-mingw32
 
@@ -19,7 +20,7 @@ DEPENDENCIES
   diff-lcs (= 1.3)
   markdown_helper!
   minitest (~> 5.0)
-  rake (~> 10.0)
+  rake (~> 13.0.1)
 
 BUNDLED WITH
    1.16.1
diff --git a/markdown_helper.gemspec b/markdown_helper.gemspec
index fa1ab77..d2d1f50 100644
--- a/markdown_helper.gemspec
+++ b/markdown_helper.gemspec
@@ -36,7 +36,7 @@ EOT
   spec.require_paths = ['lib']
 
   spec.add_development_dependency 'bundler', '~> 1.14'
-  spec.add_development_dependency 'rake', '~> 12.3.2'
+  spec.add_development_dependency 'rake', '~> 13.0.1'
   spec.add_development_dependency 'minitest', '~> 5.0'
   spec.add_development_dependency 'diff-lcs', '~> 1.3'
 end