diff --git a/Gemfile b/Gemfile
index c2ef9d7..0d204e5 100644
--- a/Gemfile
+++ b/Gemfile
@@ -15,7 +15,7 @@ gem 'rails', '~> 5.0.0.1'
 gem 'rails_admin', '>= 1.0.0.rc'
 gem 'remotipart', github: 'mshibuya/remotipart'
 gem 'sass-rails', '~> 5.0'
-gem 'simple_form', '~> 3.2', '>= 3.2.1'
+gem 'simple_form', '~> 5.0'
 gem 'turbolinks', '~> 5'
 gem 'uglifier', '>= 1.3.0'
 
diff --git a/Gemfile.lock b/Gemfile.lock
index 970b57f..8d45b86 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -56,7 +56,7 @@ GEM
     bootstrap-sass (3.3.7)
       autoprefixer-rails (>= 5.2.1)
       sass (>= 3.3.4)
-    builder (3.2.2)
+    builder (3.2.4)
     byebug (9.0.5)
     climate_control (0.0.3)
       activesupport (>= 3.0)
@@ -73,7 +73,8 @@ GEM
       coffee-script-source
       execjs
     coffee-script-source (1.10.0)
-    concurrent-ruby (1.0.2)
+    concurrent-ruby (1.1.7)
+    crass (1.0.6)
     database_cleaner (1.5.3)
     debug_inspector (0.0.2)
     devise (4.2.0)
@@ -103,7 +104,8 @@ GEM
       tilt
     http-cookie (1.0.2)
       domain_name (~> 0.5)
-    i18n (0.7.0)
+    i18n (0.9.5)
+      concurrent-ruby (~> 1.0)
     jquery-rails (4.1.1)
       rails-dom-testing (>= 1, < 3)
       railties (>= 4.2.0)
@@ -117,7 +119,8 @@ GEM
     listen (3.0.8)
       rb-fsevent (~> 0.9, >= 0.9.4)
       rb-inotify (~> 0.9, >= 0.9.7)
-    loofah (2.0.3)
+    loofah (2.7.0)
+      crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     mail (2.6.4)
       mime-types (>= 1.16, < 4)
@@ -126,14 +129,13 @@ GEM
       mime-types-data (~> 3.2015)
     mime-types-data (3.2016.0521)
     mimemagic (0.3.0)
-    mini_portile2 (2.1.0)
-    minitest (5.9.0)
+    mini_portile2 (2.4.0)
+    minitest (5.14.2)
     nested_form (0.3.2)
     netrc (0.11.0)
     nio4r (1.2.1)
-    nokogiri (1.6.8)
-      mini_portile2 (~> 2.1.0)
-      pkg-config (~> 1.1.7)
+    nokogiri (1.10.10)
+      mini_portile2 (~> 2.4.0)
     orm_adapter (0.5.0)
     paperclip (4.3.7)
       activemodel (>= 3.2.0)
@@ -144,13 +146,12 @@ GEM
     paperclip-cloudinary (1.3.0)
       cloudinary (~> 1.1)
     pg (0.18.4)
-    pkg-config (1.1.7)
     pry (0.10.4)
       coderay (~> 1.1.0)
       method_source (~> 0.8.1)
       slop (~> 3.4)
     puma (3.6.0)
-    rack (2.0.1)
+    rack (2.2.3)
     rack-pjax (1.0.0)
       nokogiri (~> 1.5)
       rack (>= 1.1)
@@ -172,11 +173,11 @@ GEM
       actionpack (~> 5.x)
       actionview (~> 5.x)
       activesupport (~> 5.x)
-    rails-dom-testing (2.0.1)
-      activesupport (>= 4.2.0, < 6.0)
-      nokogiri (~> 1.6.0)
-    rails-html-sanitizer (1.0.3)
-      loofah (~> 2.0)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.3.0)
+      loofah (~> 2.3)
     rails_admin (1.0.0.rc)
       builder (~> 3.1)
       coffee-rails (~> 4.0)
@@ -230,9 +231,9 @@ GEM
       sprockets (>= 2.8, < 4.0)
       sprockets-rails (>= 2.0, < 4.0)
       tilt (>= 1.1, < 3)
-    simple_form (3.2.1)
-      actionpack (> 4, < 5.1)
-      activemodel (> 4, < 5.1)
+    simple_form (5.0.2)
+      actionpack (>= 5.0)
+      activemodel (>= 5.0)
     simplecov (0.12.0)
       docile (~> 1.1.0)
       json (>= 1.8, < 3)
@@ -251,12 +252,12 @@ GEM
       activesupport (>= 4.0)
       sprockets (>= 3.0.0)
     thor (0.19.1)
-    thread_safe (0.3.5)
+    thread_safe (0.3.6)
     tilt (2.0.5)
     turbolinks (5.0.1)
       turbolinks-source (~> 5)
     turbolinks-source (5.0.0)
-    tzinfo (1.2.2)
+    tzinfo (1.2.7)
       thread_safe (~> 0.1)
     uglifier (3.0.1)
       execjs (>= 0.3.0, < 3)
@@ -300,7 +301,7 @@ DEPENDENCIES
   remotipart!
   rspec-rails (~> 3.5, >= 3.5.1)
   sass-rails (~> 5.0)
-  simple_form (~> 3.2, >= 3.2.1)
+  simple_form (~> 5.0)
   simplecov (~> 0.12.0)
   spring
   spring-watcher-listen (~> 2.0.0)