diff --git a/libs/binder/tests/Android.bp b/libs/binder/tests/Android.bp
index 8faa3b8..565f88e 100644
--- a/libs/binder/tests/Android.bp
+++ b/libs/binder/tests/Android.bp
@@ -84,7 +84,7 @@
             enabled: false,
         },
     },
-    srcs: ["binderParcelUnitTest.cpp"],
+    srcs: ["binderParcelUnitTest.cpp", "binderBinderUnitTest.cpp"],
     shared_libs: [
         "libbinder",
         "libutils",
diff --git a/libs/binder/tests/binderBinderUnitTest.cpp b/libs/binder/tests/binderBinderUnitTest.cpp
new file mode 100644
index 0000000..1be0c59
--- /dev/null
+++ b/libs/binder/tests/binderBinderUnitTest.cpp
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include <binder/Binder.h>
+#include <binder/IBinder.h>
+#include <gtest/gtest.h>
+
+using android::BBinder;
+using android::OK;
+using android::sp;
+
+const void* kObjectId1 = reinterpret_cast<const void*>(1);
+const void* kObjectId2 = reinterpret_cast<const void*>(2);
+void* kObject1 = reinterpret_cast<void*>(101);
+void* kObject2 = reinterpret_cast<void*>(102);
+void* kObject3 = reinterpret_cast<void*>(103);
+
+TEST(Binder, AttachObject) {
+    auto binder = sp<BBinder>::make();
+    EXPECT_EQ(nullptr, binder->attachObject(kObjectId1, kObject1, nullptr, nullptr));
+    EXPECT_EQ(nullptr, binder->attachObject(kObjectId2, kObject2, nullptr, nullptr));
+    EXPECT_EQ(kObject1, binder->attachObject(kObjectId1, kObject3, nullptr, nullptr));
+}
+
+TEST(Binder, DetachObject) {
+    auto binder = sp<BBinder>::make();
+    EXPECT_EQ(nullptr, binder->attachObject(kObjectId1, kObject1, nullptr, nullptr));
+    EXPECT_EQ(kObject1, binder->detachObject(kObjectId1));
+    EXPECT_EQ(nullptr, binder->attachObject(kObjectId1, kObject2, nullptr, nullptr));
+}