diff --git a/extra/sass-mode.el b/extra/sass-mode.el
index 837b2d76..6bb50cb4 100644
--- a/extra/sass-mode.el
+++ b/extra/sass-mode.el
@@ -72,6 +72,7 @@ text nested beneath them.")
 (defconst sass-syntax-table
   (let ((st (make-syntax-table)))
     (modify-syntax-entry ?- "w" st)
+    (modify-syntax-entry ?_ "w" st)
     st))
 
 (defconst sass-script-syntax-table