diff --git a/kivy/core/window/__init__.py b/kivy/core/window/__init__.py
index 3daab8a83..40276607b 100644
--- a/kivy/core/window/__init__.py
+++ b/kivy/core/window/__init__.py
@@ -293,7 +293,7 @@ class WindowBase(EventDispatcher):
         # XXX FIXME use late binding
         from kivy.graphics.opengl import glClearColor, glClear, \
             GL_COLOR_BUFFER_BIT, GL_DEPTH_BUFFER_BIT
-        glClearColor(1, 0, 1, 1)
+        glClearColor(0, 0, 0, 0)
         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
 
     def to_widget(self, x, y, initial=True, relative=False):