diff --git a/Gemfile b/Gemfile
index 1c09e1346b0063c4eda438784924f595ea32ca9e..324fcf0ba4f8e4aa0ff7173cebad850683f3c477 100644
--- a/Gemfile
+++ b/Gemfile
@@ -48,7 +48,7 @@ gem 'omniauth-rails_csrf_protection', '~> 0.1'
 
 gem 'color_diff', '~> 0.1'
 gem 'discard', '~> 1.2'
-gem 'doorkeeper', '~> 5.4'
+gem 'doorkeeper', '~> 5.5'
 gem 'ed25519', '~> 1.2'
 gem 'fast_blank', '~> 1.0'
 gem 'fastimage'
diff --git a/Gemfile.lock b/Gemfile.lock
index 21b3ddf39a4d128c74123b4e63114e65f6e455b7..17ca9a26e7c0975b3feff1462311efef3c14ab66 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -187,7 +187,7 @@ GEM
     docile (1.3.4)
     domain_name (0.5.20190701)
       unf (>= 0.0.5, < 1.0.0)
-    doorkeeper (5.4.0)
+    doorkeeper (5.5.0)
       railties (>= 5)
     dotenv (2.7.6)
     dotenv-rails (2.7.6)
@@ -717,7 +717,7 @@ DEPENDENCIES
   devise-two-factor (~> 3.1)
   devise_pam_authenticatable2 (~> 9.2)
   discard (~> 1.2)
-  doorkeeper (~> 5.4)
+  doorkeeper (~> 5.5)
   dotenv-rails (~> 2.7)
   ed25519 (~> 1.2)
   fabrication (~> 2.21)