diff --git a/ets2panda/checker/ets/typeCheckingHelpers.cpp b/ets2panda/checker/ets/typeCheckingHelpers.cpp
index e000739bc0271af8848248f4ebb6184a9c4d7771..7d1bdcdb6f1b5e31ba387ddd014d84f525449b02 100644
--- a/ets2panda/checker/ets/typeCheckingHelpers.cpp
+++ b/ets2panda/checker/ets/typeCheckingHelpers.cpp
@@ -1076,11 +1076,13 @@ void ETSChecker::ValidateThisUsage(const ir::TypeNode *returnTypeAnnotation)
     }
     if (returnTypeAnnotation->IsETSTypeReference() &&
         IsFixedArray(returnTypeAnnotation->AsETSTypeReference()->Part())) {
-        auto elementType = returnTypeAnnotation->AsETSTypeReference()->Part()->TypeParams()->Params()[0];
-        if (CheckAndLogInvalidThisUsage(elementType, diagnostic::NOT_ALLOWED_THIS_IN_ARRAY_TYPE)) {
-            return;
+        if (returnTypeAnnotation->AsETSTypeReference()->Part()->TypeParams() != nullptr) {
+            auto elementType = returnTypeAnnotation->AsETSTypeReference()->Part()->TypeParams()->Params()[0];
+            if (CheckAndLogInvalidThisUsage(elementType, diagnostic::NOT_ALLOWED_THIS_IN_ARRAY_TYPE)) {
+                return;
+            }
+            ValidateThisUsage(elementType);
         }
-        ValidateThisUsage(elementType);
         return;
     }
 }
diff --git a/ets2panda/test/ast/compiler/ets/returnTypeAnnotation_typeParams_nullptr.ets b/ets2panda/test/ast/compiler/ets/returnTypeAnnotation_typeParams_nullptr.ets
new file mode 100755
index 0000000000000000000000000000000000000000..6308a2528182ffca7f69fce93dbb8f1a8c72e2d1
--- /dev/null
+++ b/ets2panda/test/ast/compiler/ets/returnTypeAnnotation_typeParams_nullptr.ets
@@ -0,0 +1,25 @@
+/*
+ * 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: *
+ * 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.
+ */
+
+class Arr<T> {
+	public mp<U>(a: int): FixedArray<()> 
+}
+
+/* @@? 16:11 Error TypeError: Only abstract or native methods can't have body. */
+/* @@? 16:24 Error TypeError: FixedArray<T> must have only one type parameter. */
+/* @@? 16:37 Error SyntaxError: Unexpected token, expected '=>'. */
+/* @@? 16:37 Error SyntaxError: Unexpected token, expected '('. */
+/* @@? 16:37 Error SyntaxError: Invalid Type. */
+/* @@? 16:37 Error SyntaxError: Unexpected token, expected '>'. */
+/* @@? 16:37 Error SyntaxError: Unexpected token '>'. */
\ No newline at end of file