diff --git a/ets2panda/compiler/base/lreference.cpp b/ets2panda/compiler/base/lreference.cpp
index a047c992aa488e77e5e29063dec0bab15d1340bf..8fa1c8ab96078f66734503421236d1189252cf51 100644
--- a/ets2panda/compiler/base/lreference.cpp
+++ b/ets2panda/compiler/base/lreference.cpp
@@ -365,7 +365,7 @@ void ETSLReference::SetValue() const
     }
 
     if (objectType->IsETSUnionType()) {
-        etsg_->StoreUnionProperty(Node(), baseReg_, propName);
+        etsg_->StoreUnionProperty(Node(), memberExprTsType, baseReg_, propName);
         return;
     }
 
diff --git a/ets2panda/compiler/core/ETSGen.cpp b/ets2panda/compiler/core/ETSGen.cpp
index 54425151d3a10cfb4cb5897830123d45ba336873..a5094b8d8ed59769b256c2534c358e4f97218632 100644
--- a/ets2panda/compiler/core/ETSGen.cpp
+++ b/ets2panda/compiler/core/ETSGen.cpp
@@ -464,11 +464,18 @@ void ETSGen::LoadProperty(const ir::AstNode *const node, const checker::Type *pr
     SetAccumulatorType(propType);
 }
 
-void ETSGen::StoreUnionProperty([[maybe_unused]] const ir::AstNode *node, [[maybe_unused]] VReg objReg,
+void ETSGen::StoreUnionProperty([[maybe_unused]] const ir::AstNode *node,
+                                [[maybe_unused]] const checker::Type *propType, [[maybe_unused]] VReg objReg,
                                 [[maybe_unused]] const util::StringView &propName)
 {
 #ifdef PANDA_WITH_ETS
-    Ra().Emit<EtsStobjName>(node, objReg, propName);
+    if (propType->HasTypeFlag(TYPE_FLAG_BYTECODE_REF)) {
+        Ra().Emit<EtsStobjNameObj>(node, objReg, propName);
+    } else if (propType->HasTypeFlag(checker::TypeFlag::ETS_WIDE_NUMERIC)) {
+        Ra().Emit<EtsStobjNameWide>(node, objReg, propName);
+    } else {
+        Ra().Emit<EtsStobjName>(node, objReg, propName);
+    }
 #else
     UNREACHABLE();
 #endif  // PANDA_WITH_ETS
@@ -479,7 +486,13 @@ void ETSGen::LoadUnionProperty([[maybe_unused]] const ir::AstNode *const node,
                                [[maybe_unused]] const util::StringView &propName)
 {
 #ifdef PANDA_WITH_ETS
-    Ra().Emit<EtsLdobjName>(node, objReg, propName);
+    if (propType->HasTypeFlag(TYPE_FLAG_BYTECODE_REF)) {
+        Ra().Emit<EtsLdobjNameObj>(node, objReg, propName);
+    } else if (propType->HasTypeFlag(checker::TypeFlag::ETS_WIDE_NUMERIC)) {
+        Ra().Emit<EtsLdobjNameWide>(node, objReg, propName);
+    } else {
+        Ra().Emit<EtsLdobjName>(node, objReg, propName);
+    }
     SetAccumulatorType(propType);
 #else
     UNREACHABLE();
diff --git a/ets2panda/compiler/core/ETSGen.h b/ets2panda/compiler/core/ETSGen.h
index b06ec78733004e7fb184246f7c6b96d7c5bff304..f4cf2f43dc84b449a6c1087b09f710635fdb6155 100644
--- a/ets2panda/compiler/core/ETSGen.h
+++ b/ets2panda/compiler/core/ETSGen.h
@@ -77,7 +77,8 @@ public:
     void StoreElementDynamic(const ir::AstNode *node, VReg objectReg, VReg index);
     void LoadElementDynamic(const ir::AstNode *node, VReg objectReg);
 
-    void StoreUnionProperty(const ir::AstNode *node, VReg objReg, const util::StringView &propName);
+    void StoreUnionProperty(const ir::AstNode *node, const checker::Type *propType, VReg objReg,
+                            const util::StringView &propName);
     void LoadUnionProperty(const ir::AstNode *node, const checker::Type *propType, VReg objReg,
                            const util::StringView &propName);
 
diff --git a/ets2panda/test/runtime/ets/union_wide_property_access.ets b/ets2panda/test/runtime/ets/union_wide_property_access.ets
new file mode 100644
index 0000000000000000000000000000000000000000..1a496dcc79b3993efd8aeba4a2a21a7327c64145
--- /dev/null
+++ b/ets2panda/test/runtime/ets/union_wide_property_access.ets
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2024 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 A { memb: number = 2; }
+class B { memb: number = 6; }
+class C { memb: A|B = new A(); }
+
+function bar(a0: A | B): void {
+    a0.memb = 50;
+}
+
+function foo(arr: Int8Array | Int16Array): void {
+    let len = arr.length
+    assert len == 42;
+}
+
+function main() {
+    let buffer: ArrayBuffer = new ArrayBuffer(42);
+    let byteArr: Int8Array= new Int8Array(buffer)
+    foo(byteArr);
+    assert byteArr.length == 42;
+
+    let ab: A|B = new A();
+    bar(ab);
+    assert ab.memb == 50
+
+    let cClass: C = new C();
+    cClass.memb = new B();
+    assert cClass.memb.memb == 6;
+}
diff --git a/ets2panda/test/test-lists/ets-runtime/ets-runtime-ignored.txt b/ets2panda/test/test-lists/ets-runtime/ets-runtime-ignored.txt
index 7b6b2e0d97a8ed83bdb97e21f71a9007f3265ae9..b766e9e536ddca7bb1300e18b5745349f86bd8de 100644
--- a/ets2panda/test/test-lists/ets-runtime/ets-runtime-ignored.txt
+++ b/ets2panda/test/test-lists/ets-runtime/ets-runtime-ignored.txt
@@ -58,5 +58,9 @@ lambdaExpressionWithRestParameter.ets
 castSequence.ets
 
 # ignored due to interface implementation modification
-local-class-standard-example1.ets 
+local-class-standard-example1.ets
 local-class-standard-example2.ets
+
+# verifier false positive for 64 bit instructions on union types.
+# Issue: #16216
+union_wide_property_access.ets