diff --git a/mode/conf.py b/mode/conf.py
index b1c4067..3fc85d2 100644
--- a/mode/conf.py
+++ b/mode/conf.py
@@ -5,6 +5,7 @@ from mode.sh import StringGrammar
 class ConfGrammar(Grammar):
     rules = [
         PatternRule(r'comment', r'#.*$'),
+        PatternRule(r'comment', r'//.*$'),
         RegionRule(r'string', r"'", Grammar, r"'"),
         RegionRule(r'string', r'"', StringGrammar, r'"'),
     ]