diff --git a/src/renderers/WebGLRenderer.js b/src/renderers/WebGLRenderer.js
index 81fd25adb029b587f369b71b11354e70bfb5ff19..9d466f87c68b531061286290f9b5ec268183a4be 100644
--- a/src/renderers/WebGLRenderer.js
+++ b/src/renderers/WebGLRenderer.js
@@ -2512,7 +2512,7 @@ function WebGLRenderer( parameters ) {
 
 		var framebuffer = properties.get( renderTarget ).__webglFramebuffer;
 
-		if ( activeCubeFaceIndex != undefined ) {
+		if ( renderTarget.isWebGLRenderTargetCube && activeCubeFaceIndex != undefined ) {
 
 			framebuffer = framebuffer[ activeCubeFaceIndex ];