diff --git a/CHANGELOG.md b/CHANGELOG.md
index f4faeef9d..6f024e744 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@ All notable changes to this project will be documented in this file. For info on
 
 ### Fixed
 
+- TempfileReaper now deletes temp files if application raises an exception. ([#1679](https://github.com/rack/rack/issues/1679), [@jeremyevans](https://github.com/jeremyevans))
 - Fix using Rack::Session::Cookie with coder: Rack::Session::Cookie::Base64::{JSON,Zip}. ([#1666](https://github.com/rack/rack/issues/1666), [@jeremyevans](https://github.com/jeremyevans))
 - Avoid NoMethodError when accessing Rack::Session::Cookie without requiring delegate first. ([#1610](https://github.com/rack/rack/issues/1610), [@onigra](https://github.com/onigra))
 - Handle cookies with values that end in '=' ([#1645](https://github.com/rack/rack/pull/1645), [@lukaso](https://github.com/lukaso))
diff --git a/lib/rack/tempfile_reaper.rb b/lib/rack/tempfile_reaper.rb
index 9b04fefc2..12500f0a9 100644
--- a/lib/rack/tempfile_reaper.rb
+++ b/lib/rack/tempfile_reaper.rb
@@ -12,7 +12,14 @@ def initialize(app)
 
     def call(env)
       env[RACK_TEMPFILES] ||= []
-      status, headers, body = @app.call(env)
+
+      begin
+        status, headers, body = @app.call(env)
+      rescue Exception
+        env[RACK_TEMPFILES].each(&:close!) unless env[RACK_TEMPFILES].nil?
+        raise
+      end
+
       body_proxy = BodyProxy.new(body) do
         env[RACK_TEMPFILES].each(&:close!) unless env[RACK_TEMPFILES].nil?
       end
diff --git a/test/spec_tempfile_reaper.rb b/test/spec_tempfile_reaper.rb
index 063687a09..4756e53ea 100644
--- a/test/spec_tempfile_reaper.rb
+++ b/test/spec_tempfile_reaper.rb
@@ -30,6 +30,24 @@ def call(app)
     response[0].must_equal 200
   end
 
+  it 'close env[rack.tempfiles] when app raises an error' do
+    tempfile1, tempfile2 = MockTempfile.new, MockTempfile.new
+    @env['rack.tempfiles'] = [ tempfile1, tempfile2 ]
+    app = lambda { |_| raise 'foo' }
+    proc{call(app)}.must_raise RuntimeError
+    tempfile1.closed.must_equal true
+    tempfile2.closed.must_equal true
+  end
+
+  it 'close env[rack.tempfiles] when app raises an non-StandardError' do
+    tempfile1, tempfile2 = MockTempfile.new, MockTempfile.new
+    @env['rack.tempfiles'] = [ tempfile1, tempfile2 ]
+    app = lambda { |_| raise LoadError, 'foo' }
+    proc{call(app)}.must_raise LoadError
+    tempfile1.closed.must_equal true
+    tempfile2.closed.must_equal true
+  end
+
   it 'close env[rack.tempfiles] when body is closed' do
     tempfile1, tempfile2 = MockTempfile.new, MockTempfile.new
     @env['rack.tempfiles'] = [ tempfile1, tempfile2 ]