diff --git a/src/parser/plugins/validate-keyword.ts b/src/parser/plugins/validate-keyword.ts
index 6c1fdac1..a179aba7 100644
--- a/src/parser/plugins/validate-keyword.ts
+++ b/src/parser/plugins/validate-keyword.ts
@@ -2,44 +2,56 @@ import { AiScriptSyntaxError } from '../../error.js';
 import { visitNode } from '../visit.js';
 import type * as Ast from '../../node.js';
 
-const reservedWord = [
-	'null',
-	'true',
-	'false',
-	'each',
-	'for',
-	'loop',
-	'break',
-	'continue',
-	'match',
-	'if',
-	'elif',
-	'else',
-	'return',
-	'eval',
-	'var',
-	'let',
-	'exists',
+// 予約語となっている識別子があるかを確認する。
+// - キーワードは字句解析の段階でそれぞれのKeywordトークンとなるため除外
+// - 文脈キーワードは識別子に利用できるため除外
 
-	// future
-	'fn',
-	'namespace',
-	'meta',
+const reservedWord = [
+	'as',
+	'async',
 	'attr',
 	'attribute',
-	'static',
+	'await',
+	'catch',
 	'class',
-	'struct',
-	'module',
-	'while',
-	'import',
-	'export',
 	// 'const',
+	'component',
+	'constructor',
 	// 'def',
+	'dictionary',
+	'do',
+	'enum',
+	'export',
+	'finally',
+	'fn',
 	// 'func',
 	// 'function',
-	// 'ref',
-	// 'out',
+	'hash',
+	'in',
+	'interface',
+	'out',
+	'private',
+	'public',
+	'ref',
+	'static',
+	'struct',
+	'table',
+	'this',
+	'throw',
+	'trait',
+	'try',
+	'undefined',
+	'use',
+	'using',
+	'when',
+	'while',
+	'yield',
+	'import',
+	'is',
+	'meta',
+	'module',
+	'namespace',
+	'new',
 ];
 
 function throwReservedWordError(name: string, loc: Ast.Loc): void {
@@ -48,10 +60,11 @@ function throwReservedWordError(name: string, loc: Ast.Loc): void {
 
 function validateNode(node: Ast.Node): Ast.Node {
 	switch (node.type) {
+		case 'ns':
 		case 'def':
 		case 'attr':
-		case 'ns':
-		case 'identifier': {
+		case 'identifier':
+		case 'prop': {
 			if (reservedWord.includes(node.name)) {
 				throwReservedWordError(node.name, node.loc);
 			}
@@ -63,6 +76,18 @@ function validateNode(node: Ast.Node): Ast.Node {
 			}
 			break;
 		}
+		case 'each': {
+			if (reservedWord.includes(node.var)) {
+				throwReservedWordError(node.var, node.loc);
+			}
+			break;
+		}
+		case 'for': {
+			if (node.var != null && reservedWord.includes(node.var)) {
+				throwReservedWordError(node.var, node.loc);
+			}
+			break;
+		}
 		case 'fn': {
 			for (const arg of node.args) {
 				if (reservedWord.includes(arg.name)) {
@@ -71,6 +96,14 @@ function validateNode(node: Ast.Node): Ast.Node {
 			}
 			break;
 		}
+		case 'obj': {
+			for (const name of node.value.keys()) {
+				if (reservedWord.includes(name)) {
+					throwReservedWordError(name, node.loc);
+				}
+			}
+			break;
+		}
 	}
 
 	return node;
diff --git a/test/index.ts b/test/index.ts
index 48cb8a6b..4fab2a0b 100644
--- a/test/index.ts
+++ b/test/index.ts
@@ -6,6 +6,7 @@
 import * as assert from 'assert';
 import { Parser, Interpreter, utils, errors, Ast } from '../src';
 import { NUM, STR, NULL, ARR, OBJ, BOOL, TRUE, FALSE, ERROR ,FN_NATIVE } from '../src/interpreter/value';
+import { AiScriptSyntaxError } from '../src/error';
 let { AiScriptRuntimeError, AiScriptIndexOutOfRangeError } = errors;
 
 const exe = (program: string): Promise<any> => new Promise((ok, err) => {
@@ -2886,7 +2887,7 @@ describe('Security', () => {
 			`);
 			assert.fail();
 		} catch (e) {
-			assert.ok(e instanceof AiScriptRuntimeError);
+			assert.ok(e instanceof AiScriptSyntaxError);
 		}
 
 		try {
@@ -2909,13 +2910,6 @@ describe('Security', () => {
 	});
 
 	test.concurrent('Cannot access js native property via object', async () => {
-		const res1 = await exe(`
-		let obj = {}
-
-		<: obj.constructor
-		`);
-		eq(res1, NULL);
-
 		const res2 = await exe(`
 		let obj = {}
 
@@ -2938,7 +2932,7 @@ describe('Security', () => {
 			`);
 			assert.fail();
 		} catch (e) {
-			assert.ok(e instanceof AiScriptRuntimeError);
+			assert.ok(e instanceof AiScriptSyntaxError);
 		}
 
 		try {