diff --git a/src/xfaces.c b/src/xfaces.c
index c562ce3b592..c02295c7a27 100644
--- a/src/xfaces.c
+++ b/src/xfaces.c
@@ -4148,7 +4148,7 @@ FRAME 0 means change the face on all frames, and change the default
 		}
 	      else if (EQ (k, QCcolor))
 		{
-		  if (!STRINGP (v) || SCHARS (v) == 0)
+		  if (!NILP (v) && (!STRINGP (v) || SCHARS (v) == 0))
 		    break;
 		}
 	      else if (EQ (k, QCstyle))