diff --git a/media/libheadtracking/ScreenHeadFusion-test.cpp b/media/libheadtracking/ScreenHeadFusion-test.cpp
new file mode 100644
index 0000000..ecf27f5
--- /dev/null
+++ b/media/libheadtracking/ScreenHeadFusion-test.cpp
@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2021 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 <gtest/gtest.h>
+
+#include "ScreenHeadFusion.h"
+#include "TestUtil.h"
+
+using Eigen::Quaternionf;
+using Eigen::Vector3f;
+
+namespace android {
+namespace media {
+namespace {
+
+TEST(ScreenHeadFusion, Init) {
+    ScreenHeadFusion fusion;
+    EXPECT_FALSE(fusion.calculate().has_value());
+}
+
+TEST(ScreenHeadFusion, Calculate_NoHead) {
+    ScreenHeadFusion fusion;
+    fusion.setWorldToScreenPose(0, Pose3f());
+    EXPECT_FALSE(fusion.calculate().has_value());
+}
+
+TEST(ScreenHeadFusion, Calculate_NoScreen) {
+    ScreenHeadFusion fusion;
+    fusion.setWorldToHeadPose(0, Pose3f());
+    EXPECT_FALSE(fusion.calculate().has_value());
+}
+
+TEST(ScreenHeadFusion, Calculate) {
+    Pose3f worldToScreen1({1, 2, 3}, Quaternionf::UnitRandom());
+    Pose3f worldToHead1({4, 5, 6}, Quaternionf::UnitRandom());
+    Pose3f worldToScreen2({11, 12, 13}, Quaternionf::UnitRandom());
+    Pose3f worldToHead2({14, 15, 16}, Quaternionf::UnitRandom());
+
+    ScreenHeadFusion fusion;
+    fusion.setWorldToHeadPose(123, worldToHead1);
+    fusion.setWorldToScreenPose(456, worldToScreen1);
+    auto result = fusion.calculate();
+    ASSERT_TRUE(result.has_value());
+    EXPECT_EQ(123, result->timestamp);
+    EXPECT_EQ(worldToScreen1.inverse() * worldToHead1, result->pose);
+
+    fusion.setWorldToHeadPose(567, worldToHead2);
+    result = fusion.calculate();
+    ASSERT_TRUE(result.has_value());
+    EXPECT_EQ(456, result->timestamp);
+    EXPECT_EQ(worldToScreen1.inverse() * worldToHead2, result->pose);
+
+    fusion.setWorldToScreenPose(678, worldToScreen2);
+    result = fusion.calculate();
+    ASSERT_TRUE(result.has_value());
+    EXPECT_EQ(567, result->timestamp);
+    EXPECT_EQ(worldToScreen2.inverse() * worldToHead2, result->pose);
+}
+
+}  // namespace
+}  // namespace media
+}  // namespace android