diff --git a/package.json b/package.json
index 245ea9f3..d4fecd57 100644
--- a/package.json
+++ b/package.json
@@ -67,7 +67,7 @@
     "@changesets/get-release-plan": "^4.0.5",
     "@ota-meshi/eslint-plugin": "^0.17.6",
     "@types/benchmark": "^2.1.5",
-    "@types/chai": "^4.3.20",
+    "@types/chai": "^5.0.0",
     "@types/eslint": "^9.6.1",
     "@types/eslint-scope": "^3.7.7",
     "@types/eslint-visitor-keys": "^3.3.2",
@@ -79,7 +79,7 @@
     "@typescript-eslint/parser": "~8.16.0",
     "@typescript-eslint/types": "~8.16.0",
     "benchmark": "^2.1.4",
-    "chai": "^4.5.0",
+    "chai": "^5.0.0",
     "env-cmd": "^10.1.0",
     "esbuild": "^0.24.0",
     "esbuild-register": "^3.6.0",
diff --git a/tests/src/parser/html.ts b/tests/src/parser/html.ts
index 5ec9c309..0e0cd935 100644
--- a/tests/src/parser/html.ts
+++ b/tests/src/parser/html.ts
@@ -1,4 +1,4 @@
-import chai from "chai";
+import * as chai from "chai";
 import { jestSnapshotPlugin } from "mocha-chai-jest-snapshot";
 
 import { parseAttributes } from "../../../src/parser/html";