diff --git a/actionpack/lib/action_controller/test_process.rb b/actionpack/lib/action_controller/test_process.rb
index dbaec00bee9b8..c5081a2008076 100644
--- a/actionpack/lib/action_controller/test_process.rb
+++ b/actionpack/lib/action_controller/test_process.rb
@@ -110,6 +110,7 @@ def assign_parameters(controller_path, action, parameters)
     end
 
     def recycle!
+      @env["action_controller.request.request_parameters"] = {}
       self.query_parameters   = {}
       self.path_parameters    = {}
       @headers, @request_method, @accepts, @content_type = nil, nil, nil, nil
diff --git a/actionpack/test/controller/test_test.rb b/actionpack/test/controller/test_test.rb
index 65c894c2e785b..3924b282d4204 100644
--- a/actionpack/test/controller/test_test.rb
+++ b/actionpack/test/controller/test_test.rb
@@ -515,6 +515,14 @@ def test_header_properly_reset_after_get_request
     assert_nil @request.instance_variable_get("@request_method")
   end
 
+  def test_params_reset_after_post_request
+    post :no_op, :foo => "bar"
+    assert_equal "bar", @request.params[:foo]
+    @request.recycle!
+    post :no_op
+    assert @request.params[:foo].blank?
+  end
+
   %w(controller response request).each do |variable|
     %w(get post put delete head process).each do |method|
       define_method("test_#{variable}_missing_for_#{method}_raises_error") do