diff --git a/languages.json b/languages.json
index 2c0c1614c..483524261 100644
--- a/languages.json
+++ b/languages.json
@@ -1074,7 +1074,7 @@
     "MoonBit": {
       "line_comment": ["//"],
       "quotes": [["\\\"", "\\\""]],
-      "extensions": ["mbt"]
+      "extensions": ["mbt", "mbti"]
     },
     "MoonScript": {
       "line_comment": ["--"],