diff --git a/services/core/java/com/android/server/wm/TaskDisplayArea.java b/services/core/java/com/android/server/wm/TaskDisplayArea.java
index 7e784ae6e2ea2..901f14f346055 100644
--- a/services/core/java/com/android/server/wm/TaskDisplayArea.java
+++ b/services/core/java/com/android/server/wm/TaskDisplayArea.java
@@ -798,12 +798,9 @@ final class TaskDisplayArea extends DisplayArea<WindowContainer> {
         int layer = 0;
         // Place root home tasks to the bottom.
         layer = adjustRootTaskLayer(t, mTmpHomeChildren, layer);
-        adjustRootTaskLayer(t, mTmpNormalChildren, layer);
-
-        // Always on top tasks layer should higher than split divider layer so set it as start.
-        t.setLayer(mSplitScreenDividerAnchor, SPLIT_DIVIDER_LAYER);
-        layer = SPLIT_DIVIDER_LAYER + 1;
+        layer = adjustRootTaskLayer(t, mTmpNormalChildren, layer);
         adjustRootTaskLayer(t, mTmpAlwaysOnTopChildren, layer);
+        t.setLayer(mSplitScreenDividerAnchor, SPLIT_DIVIDER_LAYER);
     }
 
     /**
@@ -818,19 +815,33 @@ final class TaskDisplayArea extends DisplayArea<WindowContainer> {
             ArrayList<WindowContainer> children, int startLayer) {
         mTmpNeedsZBoostIndexes.clear();
         final int childCount = children.size();
+        boolean hasAdjacentTask = false;
         for (int i = 0; i < childCount; i++) {
             final WindowContainer child = children.get(i);
             final TaskDisplayArea childTda = child.asTaskDisplayArea();
-
-            boolean childNeedsZBoost = childTda != null
+            final boolean childNeedsZBoost = childTda != null
                     ? childTda.childrenNeedZBoost()
                     : child.needsZBoost();
 
-            if (!childNeedsZBoost) {
-                child.assignLayer(t, startLayer++);
-            } else {
+            if (childNeedsZBoost) {
                 mTmpNeedsZBoostIndexes.add(i);
+                continue;
             }
+
+            final Task childTask = child.asTask();
+            final boolean inAdjacentTask = childTask != null
+                    && child.inMultiWindowMode()
+                    && childTask.getRootTask().getAdjacentTaskFragment() != null;
+
+            if (inAdjacentTask || child.inSplitScreenWindowingMode()) {
+                hasAdjacentTask = true;
+            } else if (hasAdjacentTask && startLayer < SPLIT_DIVIDER_LAYER) {
+                // Task on top of adjacent tasks should be higher than split divider layer so
+                // set it as start.
+                startLayer = SPLIT_DIVIDER_LAYER + 1;
+            }
+
+            child.assignLayer(t, startLayer++);
         }
 
         final int zBoostSize = mTmpNeedsZBoostIndexes.size();
diff --git a/services/tests/wmtests/src/com/android/server/wm/ZOrderingTests.java b/services/tests/wmtests/src/com/android/server/wm/ZOrderingTests.java
index 6c3a1f6790205..dfbdedee37c46 100644
--- a/services/tests/wmtests/src/com/android/server/wm/ZOrderingTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/ZOrderingTests.java
@@ -23,7 +23,6 @@ import static android.app.WindowConfiguration.WINDOWING_MODE_FULLSCREEN;
 import static android.app.WindowConfiguration.WINDOWING_MODE_MULTI_WINDOW;
 import static android.app.WindowConfiguration.WINDOWING_MODE_PINNED;
 import static android.app.WindowConfiguration.WINDOWING_MODE_SPLIT_SCREEN_PRIMARY;
-import static android.app.WindowConfiguration.WINDOWING_MODE_SPLIT_SCREEN_SECONDARY;
 import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION;
 import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_ABOVE_SUB_PANEL;
 import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_ATTACHED_DIALOG;
@@ -469,24 +468,42 @@ public class ZOrderingTests extends WindowTestsBase {
 
     @Test
     public void testDockedDividerPosition() {
-        final WindowState pinnedStackWindow = createWindow(null, WINDOWING_MODE_PINNED,
-                ACTIVITY_TYPE_STANDARD, TYPE_BASE_APPLICATION, mDisplayContent,
-                "pinnedStackWindow");
-        final WindowState splitScreenWindow = createWindow(null,
-                WINDOWING_MODE_SPLIT_SCREEN_PRIMARY, ACTIVITY_TYPE_STANDARD, TYPE_BASE_APPLICATION,
-                mDisplayContent, "splitScreenWindow");
-        final WindowState splitScreenSecondaryWindow = createWindow(null,
-                WINDOWING_MODE_SPLIT_SCREEN_SECONDARY, ACTIVITY_TYPE_STANDARD,
-                TYPE_BASE_APPLICATION, mDisplayContent, "splitScreenSecondaryWindow");
-        final WindowState assistantStackWindow = createWindow(null,
-                WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_ASSISTANT, TYPE_BASE_APPLICATION,
-                mDisplayContent, "assistantStackWindow");
+        final Task pinnedTask =
+                createTask(mDisplayContent, WINDOWING_MODE_PINNED, ACTIVITY_TYPE_STANDARD);
+        final WindowState pinnedWindow =
+                createAppWindow(pinnedTask, ACTIVITY_TYPE_STANDARD, "pinnedWindow");
+
+        final Task belowTask =
+                createTask(mDisplayContent, WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_STANDARD);
+        final WindowState belowTaskWindow =
+                createAppWindow(belowTask, ACTIVITY_TYPE_STANDARD, "belowTaskWindow");
+
+        final Task splitScreenTask1 =
+                createTask(mDisplayContent, WINDOWING_MODE_MULTI_WINDOW, ACTIVITY_TYPE_STANDARD);
+        final WindowState splitWindow1 =
+                createAppWindow(splitScreenTask1, ACTIVITY_TYPE_STANDARD, "splitWindow1");
+        final Task splitScreenTask2 =
+                createTask(mDisplayContent, WINDOWING_MODE_MULTI_WINDOW, ACTIVITY_TYPE_STANDARD);
+        final WindowState splitWindow2 =
+                createAppWindow(splitScreenTask2, ACTIVITY_TYPE_STANDARD, "splitWindow2");
+        splitScreenTask1.setAdjacentTaskFragment(splitScreenTask2);
+        splitScreenTask2.setAdjacentTaskFragment(splitScreenTask1);
+
+        final Task aboveTask =
+                createTask(mDisplayContent, WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_STANDARD);
+        final WindowState aboveTaskWindow =
+                createAppWindow(aboveTask, ACTIVITY_TYPE_STANDARD, "aboveTaskWindow");
 
         mDisplayContent.assignChildLayers(mTransaction);
 
-        assertWindowHigher(mDockedDividerWindow, splitScreenWindow);
-        assertWindowHigher(mDockedDividerWindow, splitScreenSecondaryWindow);
-        assertWindowHigher(pinnedStackWindow, mDockedDividerWindow);
+        assertWindowHigher(splitWindow1, belowTaskWindow);
+        assertWindowHigher(splitWindow1, belowTaskWindow);
+        assertWindowHigher(splitWindow2, belowTaskWindow);
+        assertWindowHigher(splitWindow2, belowTaskWindow);
+        assertWindowHigher(mDockedDividerWindow, splitWindow1);
+        assertWindowHigher(mDockedDividerWindow, splitWindow2);
+        assertWindowHigher(aboveTaskWindow, mDockedDividerWindow);
+        assertWindowHigher(pinnedWindow, aboveTaskWindow);
     }
 
     @Test