diff --git a/.github/workflows/NodeCI.yml b/.github/workflows/NodeCI.yml
index e01f8e7d..c5ced881 100644
--- a/.github/workflows/NodeCI.yml
+++ b/.github/workflows/NodeCI.yml
@@ -33,6 +33,25 @@ jobs:
       run: npm install
     - name: Test
       run: npm test
+  test-for-ts-eslint-v4:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node-version: [14.x]
+    steps:
+    - uses: actions/checkout@v2
+    - name: Use Node.js ${{ matrix.node-version }}
+      uses: actions/setup-node@v2
+      with:
+        node-version: ${{ matrix.node-version }}
+    - name: Install @typescript-eslint v4
+      run: |+
+        npm i -D @typescript-eslint/parser@4 @typescript-eslint/eslint-plugin@4 --legacy-peer-deps
+        npx rimraf node_modules
+    - name: Install Packages
+      run: npm install
+    - name: Test
+      run: npm test
   test-and-coverage:
     runs-on: ubuntu-latest
     steps:
diff --git a/package.json b/package.json
index c9fb64a8..042cd1a7 100644
--- a/package.json
+++ b/package.json
@@ -51,8 +51,8 @@
         "@types/eslint-visitor-keys": "^1.0.0",
         "@types/mocha": "^9.0.0",
         "@types/node": "^14.0.13",
-        "@typescript-eslint/eslint-plugin": "^4.9.1",
-        "@typescript-eslint/parser": "^4.9.1",
+        "@typescript-eslint/eslint-plugin": "^5.0.0",
+        "@typescript-eslint/parser": "^5.0.0",
         "code-red": "^0.2.0",
         "eslint": "^7.5.0",
         "eslint-config-prettier": "^8.0.0",
diff --git a/src/context/script-let.ts b/src/context/script-let.ts
index 5b0c03a6..c991b809 100644
--- a/src/context/script-let.ts
+++ b/src/context/script-let.ts
@@ -14,6 +14,18 @@ import type { ESLintExtendedProgram } from "../parser"
 import { getWithLoc } from "../parser/converts/common"
 import { traverseNodes } from "../traverse"
 
+type TSAsExpression = {
+    type: "TSAsExpression"
+    expression: ESTree.Expression
+    typeAnnotation: TSParenthesizedType | ESTree.Node
+}
+
+// TS ESLint v4 Node
+type TSParenthesizedType = {
+    type: "TSParenthesizedType"
+    typeAnnotation: ESTree.Node
+}
+
 export type ScriptLetCallback<E extends ESTree.Node> = (
     es: E,
     options: ScriptLetCallbackOption,
@@ -117,9 +129,11 @@ export class ScriptLetContext {
             range[0] - 1,
             (st, tokens, comments, result) => {
                 const exprSt = st as ESTree.ExpressionStatement
-                const node: ESTree.Expression = isTS
-                    ? (exprSt.expression as any).expression
-                    : exprSt.expression
+                const tsAs: TSAsExpression | null = isTS
+                    ? (exprSt.expression as any)
+                    : null
+                const node: ESTree.Expression =
+                    tsAs?.expression || exprSt.expression
                 // Process for nodes
                 for (const callback of callbacks) {
                     callback(node as E, result)
@@ -134,8 +148,9 @@ export class ScriptLetContext {
                     removeScope(
                         result.scopeManager,
                         result.getScope(
-                            (exprSt.expression as any).typeAnnotation
-                                .typeAnnotation,
+                            tsAs!.typeAnnotation.type === "TSParenthesizedType"
+                                ? tsAs!.typeAnnotation.typeAnnotation
+                                : tsAs!.typeAnnotation,
                         ),
                     )
                     this.remapNodes(