diff --git a/railties/lib/rails/application/configuration.rb b/railties/lib/rails/application/configuration.rb
index 6e31fb0ea92..aca01f216ba 100644
--- a/railties/lib/rails/application/configuration.rb
+++ b/railties/lib/rails/application/configuration.rb
@@ -43,7 +43,7 @@ module Rails
         @session_store                           = nil
         @time_zone                               = "UTC"
         @beginning_of_week                       = :monday
-        @log_level                               = :info
+        @log_level                               = :debug
         @generators                              = app_generators
         @cache_store                             = [ :file_store, "#{root}/tmp/cache/" ]
         @railties_order                          = [:all]
diff --git a/railties/test/application/configuration_test.rb b/railties/test/application/configuration_test.rb
index 5c91f480f23..679706dea6a 100644
--- a/railties/test/application/configuration_test.rb
+++ b/railties/test/application/configuration_test.rb
@@ -1577,8 +1577,15 @@ module ApplicationTests
       assert_equal session_options, app.config.session_options
     end
 
-    test "config.log_level defaults to info" do
-      make_basic_app
+    test "config.log_level defaults to debug in development" do
+      app "development"
+
+      assert_equal Logger::DEBUG, Rails.logger.level
+    end
+
+    test "config.log_level default to info in production" do
+      app "production"
+
       assert_equal Logger::INFO, Rails.logger.level
     end
 
diff --git a/railties/test/isolation/abstract_unit.rb b/railties/test/isolation/abstract_unit.rb
index 8513f3690d2..6925c95f71c 100644
--- a/railties/test/isolation/abstract_unit.rb
+++ b/railties/test/isolation/abstract_unit.rb
@@ -206,7 +206,6 @@ module TestHelpers
         config.session_store :cookie_store, key: "_myapp_session"
         config.active_support.deprecation = :log
         config.action_controller.allow_forgery_protection = false
-        config.log_level = :info
       RUBY
     end