diff --git a/ets2panda/parser/ETSparser.cpp b/ets2panda/parser/ETSparser.cpp
index 3aae7a2ec971e216fc413454e23d7175c6610f8a..33c944adee6f202213c4b983f971e5fb774122a8 100644
--- a/ets2panda/parser/ETSparser.cpp
+++ b/ets2panda/parser/ETSparser.cpp
@@ -1873,8 +1873,9 @@ ir::Expression *ETSParser::ParseExpressionOrTypeAnnotation(lexer::TokenType type
                                                            [[maybe_unused]] ExpressionParseFlags flags)
 {
     if (type == lexer::TokenType::KEYW_INSTANCEOF) {
-        TypeAnnotationParsingOptions options =
-            TypeAnnotationParsingOptions::REPORT_ERROR | TypeAnnotationParsingOptions::ANNOTATION_NOT_ALLOW;
+        TypeAnnotationParsingOptions options = TypeAnnotationParsingOptions::REPORT_ERROR |
+                                               TypeAnnotationParsingOptions::ANNOTATION_NOT_ALLOW |
+                                               TypeAnnotationParsingOptions::INSTANCEOF;
 
         if (Lexer()->GetToken().Type() == lexer::TokenType::LITERAL_NULL) {
             auto *typeAnnotation = AllocNode<ir::NullLiteral>();
diff --git a/ets2panda/parser/ETSparserTypes.cpp b/ets2panda/parser/ETSparserTypes.cpp
index 946e7611eda6860a9524045f088f7a7dd09d57ef..6df1e0310eb87b13b2377de786bc277cb523bf78 100644
--- a/ets2panda/parser/ETSparserTypes.cpp
+++ b/ets2panda/parser/ETSparserTypes.cpp
@@ -445,10 +445,13 @@ ir::TypeNode *ETSParser::ParseThisType(TypeAnnotationParsingOptions *options)
     bool parseReturnType = (*options & TypeAnnotationParsingOptions::RETURN_TYPE) != 0;
     bool isExtensionFunction = (GetContext().Status() & ParserStatus::HAS_RECEIVER) != 0;
     bool isInUnion = (*options & TypeAnnotationParsingOptions::DISALLOW_UNION) != 0;
+    bool isInstance = (*options & TypeAnnotationParsingOptions::INSTANCEOF) != 0;
     if (isExtensionFunction) {
         if (reportErr && (!IsSimpleReturnThis(Lexer()->GetToken()) || isInUnion)) {
             LogError(diagnostic::THIS_IN_NON_STATIC_METHOD, {}, startPos);
         }
+    } else if (reportErr && (isInstance)) {
+        LogError(diagnostic::INVALID_RIGHT_INSTANCEOF, {}, startPos);
     } else if (reportErr && (!allowThisType || !parseReturnType || isArrowFunc)) {
         LogError(diagnostic::THIS_IN_NON_STATIC_METHOD, {}, startPos);
     }
diff --git a/ets2panda/parser/parserImpl.h b/ets2panda/parser/parserImpl.h
index 30da9aa1ce5d3216d0d79c7e9961bf3649ddbe3c..c138f5112c602452c21c235dfa0a800a87a5752b 100644
--- a/ets2panda/parser/parserImpl.h
+++ b/ets2panda/parser/parserImpl.h
@@ -63,7 +63,8 @@ enum class TypeAnnotationParsingOptions : uint32_t {
     ALLOW_DECLARATION_SITE_VARIANCE = 1U << 14U,
     DISALLOW_UNION = 1U << 15U,
     POTENTIAL_NEW_ARRAY = 1U << 16U,
-    ANNOTATION_NOT_ALLOW = 1U << 17U
+    ANNOTATION_NOT_ALLOW = 1U << 17U,
+    INSTANCEOF = 1U << 18U
 };
 
 class ParserImpl {
diff --git a/ets2panda/test/ast/parser/ets/this_type_instanceof_invalid.ets b/ets2panda/test/ast/parser/ets/this_type_instanceof_invalid.ets
new file mode 100644
index 0000000000000000000000000000000000000000..5bc319026e5eb7a5aff2c162ad3c6d83864a21a5
--- /dev/null
+++ b/ets2panda/test/ast/parser/ets/this_type_instanceof_invalid.ets
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2025 Huawei Device Co., Ltd.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+type F = () => number;
+
+class C<T> {
+  a: T;
+  b: F;
+  constructor( a: T,  b: F) {
+    this.a = a;
+    this.b = b;
+  }
+
+
+  foo() {
+    if (this.a instanceof /* @@ label */this) {
+        return 0;
+    }
+    return 1;
+  }
+}
+
+/* @@@ label Error SyntaxError: Invalid right-hand side in 'instanceof' expression.  */