diff --git a/libs/ui/tests/Android.bp b/libs/ui/tests/Android.bp
index 032dd4c..d005ce8 100644
--- a/libs/ui/tests/Android.bp
+++ b/libs/ui/tests/Android.bp
@@ -29,6 +29,13 @@
 }
 
 cc_test {
+    name: "DisplayId_test",
+    shared_libs: ["libui"],
+    srcs: ["DisplayId_test.cpp"],
+    cflags: ["-Wall", "-Werror"],
+}
+
+cc_test {
     name: "FlattenableHelpers_test",
     shared_libs: ["libui"],
     srcs: ["FlattenableHelpers_test.cpp"],
diff --git a/libs/ui/tests/DisplayId_test.cpp b/libs/ui/tests/DisplayId_test.cpp
new file mode 100644
index 0000000..1d908b8
--- /dev/null
+++ b/libs/ui/tests/DisplayId_test.cpp
@@ -0,0 +1,66 @@
+/*
+ * Copyright 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 <ui/DisplayId.h>
+
+#include <gtest/gtest.h>
+
+namespace android::ui {
+
+TEST(DisplayIdTest, createPhysicalIdFromEdid) {
+    constexpr uint8_t port = 1;
+    constexpr uint16_t manufacturerId = 13;
+    constexpr uint32_t modelHash = 42;
+    PhysicalDisplayId id = PhysicalDisplayId::fromEdid(port, manufacturerId, modelHash);
+    EXPECT_EQ(port, id.getPort());
+    EXPECT_EQ(manufacturerId, id.getManufacturerId());
+    EXPECT_FALSE(VirtualDisplayId::tryCast(id));
+    EXPECT_FALSE(HalVirtualDisplayId::tryCast(id));
+    EXPECT_FALSE(GpuVirtualDisplayId::tryCast(id));
+    EXPECT_TRUE(PhysicalDisplayId::tryCast(id));
+    EXPECT_TRUE(HalDisplayId::tryCast(id));
+}
+
+TEST(DisplayIdTest, createPhysicalIdFromPort) {
+    constexpr uint8_t port = 3;
+    PhysicalDisplayId id = PhysicalDisplayId::fromPort(port);
+    EXPECT_EQ(port, id.getPort());
+    EXPECT_FALSE(VirtualDisplayId::tryCast(id));
+    EXPECT_FALSE(HalVirtualDisplayId::tryCast(id));
+    EXPECT_FALSE(GpuVirtualDisplayId::tryCast(id));
+    EXPECT_TRUE(PhysicalDisplayId::tryCast(id));
+    EXPECT_TRUE(HalDisplayId::tryCast(id));
+}
+
+TEST(DisplayIdTest, createGpuVirtualId) {
+    GpuVirtualDisplayId id(42);
+    EXPECT_TRUE(VirtualDisplayId::tryCast(id));
+    EXPECT_TRUE(GpuVirtualDisplayId::tryCast(id));
+    EXPECT_FALSE(HalVirtualDisplayId::tryCast(id));
+    EXPECT_FALSE(PhysicalDisplayId::tryCast(id));
+    EXPECT_FALSE(HalDisplayId::tryCast(id));
+}
+
+TEST(DisplayIdTest, createHalVirtualId) {
+    HalVirtualDisplayId id(42);
+    EXPECT_TRUE(VirtualDisplayId::tryCast(id));
+    EXPECT_TRUE(HalVirtualDisplayId::tryCast(id));
+    EXPECT_FALSE(GpuVirtualDisplayId::tryCast(id));
+    EXPECT_FALSE(PhysicalDisplayId::tryCast(id));
+    EXPECT_TRUE(HalDisplayId::tryCast(id));
+}
+
+} // namespace android::ui