diff --git a/package.json b/package.json
index 8838d09c..8fb863ef 100644
--- a/package.json
+++ b/package.json
@@ -44,7 +44,7 @@
     "@types/extend": "^3.0.4",
     "@types/mocha": "^10.0.10",
     "@types/node": "^22.13.14",
-    "@types/sinon": "^17.0.4",
+    "@types/sinon": "^21.0.0",
     "@types/uuid": "^10.0.0",
     "c8": "^10.1.3",
     "gapic-tools": "^1.0.1",