diff --git a/ets2panda/checker/ETSAnalyzer.cpp b/ets2panda/checker/ETSAnalyzer.cpp
index 9af93405a21175a9610ce64decd8a3b6ba206b65..515f962441ae17bab5115a8307d1e81a4c31139a 100644
--- a/ets2panda/checker/ETSAnalyzer.cpp
+++ b/ets2panda/checker/ETSAnalyzer.cpp
@@ -3806,6 +3806,26 @@ checker::Type *ETSAnalyzer::Check(ir::TSAsExpression *expr) const
         return expr->SetTsType(checker->TypeError(expr, diagnostic::NULLISH_CAST_TO_NONNULLISH, expr->Start()));
     }
 
+    if (expr->Expr()->IsLiteral() && sourceType->IsBuiltinNumeric() && targetType->IsETSTypeParameter()) {
+        checker->LogError(diagnostic::INVALID_CAST, {sourceType->ToString(), targetType->ToString()},
+                          expr->Expr()->Start());
+        return checker->InvalidateType(expr);
+    }
+
+    if (expr->Expr()->IsLiteral() && sourceType->IsBuiltinNumeric() && targetType->IsETSUnionType()) {
+        bool allAreTypeParams = true;
+        for (auto *sub : targetType->AsETSUnionType()->ConstituentTypes()) {
+            if (!sub->IsETSTypeParameter()) {
+                allAreTypeParams = false;
+            }
+        }
+        if (allAreTypeParams) {
+            checker->LogError(diagnostic::INVALID_CAST, {sourceType->ToString(), targetType->ToString()},
+                              expr->Expr()->Start());
+            return checker->InvalidateType(expr);
+        }
+    }
+
     const checker::CastingContext ctx(
         checker->Relation(),
         sourceType->IsBuiltinNumeric() && targetType->IsBuiltinNumeric() ? diagnostic::IMPROPER_NUMERIC_CAST
diff --git a/ets2panda/test/ast/compiler/ets/generic_method_with_default_short_neg.ets b/ets2panda/test/ast/compiler/ets/generic_method_with_default_short_neg.ets
new file mode 100644
index 0000000000000000000000000000000000000000..ee7b46aabf12ce6f2b615ef62edc6067333cf5d8
--- /dev/null
+++ b/ets2panda/test/ast/compiler/ets/generic_method_with_default_short_neg.ets
@@ -0,0 +1,28 @@
+/*
+ * 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.
+ */
+
+class Point {
+    foo<X extends short>(i:X = 0 as X): X {
+       return i;
+    }
+}
+
+function main(): void {
+    let p: Point = new Point();
+    let result: short = p.foo<short>();
+    arktest.assertEQ(result, 0 as short);       
+}
+
+/* @@? 17:32 Error TypeError: Cannot cast type 'Int' to 'X'  */
diff --git a/ets2panda/test/ast/compiler/ets/generic_method_with_promise_return_neg.ets b/ets2panda/test/ast/compiler/ets/generic_method_with_promise_return_neg.ets
new file mode 100644
index 0000000000000000000000000000000000000000..5676324ca1bd8a50b06d652ccbd11136630673ca
--- /dev/null
+++ b/ets2panda/test/ast/compiler/ets/generic_method_with_promise_return_neg.ets
@@ -0,0 +1,30 @@
+/*
+ * 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.
+ */
+
+class Point {
+    foo<X extends short>(): Promise<X> {
+       return Promise.resolve(1 as X);
+    }
+}
+
+function main(): void {
+    const p = new Point();
+    p.foo<short>().then((value: short) => {
+       arktest.assertEQ(value, 1 as short); 
+    });   
+}
+
+/* @@? 18:15 Error TypeError: Type 'Promise<*ERROR_TYPE*>' is not compatible with the enclosing method's return type 'Promise<X>'  */
+/* @@? 18:31 Error TypeError: Cannot cast type 'Int' to 'X'  */
diff --git a/ets2panda/test/ast/compiler/ets/invalid_cast_generic_type_neg_0.ets b/ets2panda/test/ast/compiler/ets/invalid_cast_generic_type_neg_0.ets
new file mode 100644
index 0000000000000000000000000000000000000000..eaf899d40ce736f4e64719fe4919d3b676c2395e
--- /dev/null
+++ b/ets2panda/test/ast/compiler/ets/invalid_cast_generic_type_neg_0.ets
@@ -0,0 +1,20 @@
+/*
+ * 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.
+ */
+
+function foo<T>() {
+    let x = 1 as T;                 
+}
+
+/* @@? 17:13 Error TypeError: Cannot cast type 'Int' to 'T'  */
diff --git a/ets2panda/test/ast/compiler/ets/invalid_cast_generic_type_neg_1.ets b/ets2panda/test/ast/compiler/ets/invalid_cast_generic_type_neg_1.ets
new file mode 100644
index 0000000000000000000000000000000000000000..030e6da0b06a8c20bc58d7100e22d6e31199acce
--- /dev/null
+++ b/ets2panda/test/ast/compiler/ets/invalid_cast_generic_type_neg_1.ets
@@ -0,0 +1,20 @@
+/*
+ * 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.
+ */
+
+function foo<T, U>() {
+    let x = 1 as (T | U);                 
+}
+
+/* @@? 17:13 Error TypeError: Cannot cast type 'Int' to 'T|U'  */
diff --git a/ets2panda/test/ast/compiler/ets/invalid_cast_generic_type_neg_2.ets b/ets2panda/test/ast/compiler/ets/invalid_cast_generic_type_neg_2.ets
new file mode 100644
index 0000000000000000000000000000000000000000..728f82f7f6b29c0eec9cdb4010f5054f0447828c
--- /dev/null
+++ b/ets2panda/test/ast/compiler/ets/invalid_cast_generic_type_neg_2.ets
@@ -0,0 +1,18 @@
+/*
+ * 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.
+ */
+
+function foo<X extends short, Y extends short>(v: X = 1 as (X | Y)){}
+
+/* @@? 16:55 Error TypeError: Cannot cast type 'Int' to 'X|Y'  */