diff --git a/packages/flutter/lib/src/material/dialog.dart b/packages/flutter/lib/src/material/dialog.dart
index 20616a8ba4..c4abe8fc08 100644
--- a/packages/flutter/lib/src/material/dialog.dart
+++ b/packages/flutter/lib/src/material/dialog.dart
@@ -526,7 +526,10 @@ class AlertDialog extends StatelessWidget {
         ),
         child: DefaultTextStyle(
           style: contentTextStyle ?? dialogTheme.contentTextStyle ?? theme.textTheme.subtitle1!,
-          child: content!,
+          child: Semantics(
+            container: true,
+            child: content!,
+          ),
         ),
       );
     }
@@ -877,7 +880,11 @@ class SimpleDialog extends StatelessWidget {
         ),
         child: DefaultTextStyle(
           style: titleTextStyle ?? DialogTheme.of(context).titleTextStyle ?? theme.textTheme.headline6!,
-          child: Semantics(namesRoute: label == null, child: title),
+          child: Semantics(
+            namesRoute: label == null,
+            container: true,
+            child: title
+          ),
         ),
       );
     }
diff --git a/packages/flutter/test/material/dialog_test.dart b/packages/flutter/test/material/dialog_test.dart
index fd8adb591f..bf09e1d29c 100644
--- a/packages/flutter/test/material/dialog_test.dart
+++ b/packages/flutter/test/material/dialog_test.dart
@@ -1341,6 +1341,71 @@ void main() {
     semantics.dispose();
   });
 
+  // Regression test for https://github.com/flutter/flutter/issues/78229.
+  testWidgets('AlertDialog has correct semantics for content in iOS', (WidgetTester tester) async {
+    final SemanticsTester semantics = SemanticsTester(tester);
+
+    await tester.pumpWidget(
+        MaterialApp(
+          theme: ThemeData(platform: TargetPlatform.iOS),
+          home: const AlertDialog(
+            title: Text('title'),
+            content: Text('content'),
+            actions: <Widget>[ TextButton(onPressed: null, child: Text('action')) ],
+          ),
+        )
+    );
+
+    expect(semantics, hasSemantics(TestSemantics.root(
+      children: <TestSemantics>[
+        TestSemantics(
+          id: 1,
+          textDirection: TextDirection.ltr,
+          children: <TestSemantics>[
+            TestSemantics(
+              id: 2,
+              children: <TestSemantics>[
+                TestSemantics(
+                  id: 3,
+                  flags: <SemanticsFlag>[SemanticsFlag.scopesRoute],
+                  children: <TestSemantics>[
+                    TestSemantics(
+                      id: 4,
+                      children: <TestSemantics>[
+                        TestSemantics(
+                          id: 5,
+                          flags: <SemanticsFlag>[SemanticsFlag.namesRoute],
+                          label: 'title',
+                          textDirection: TextDirection.ltr,
+                        ),
+                        // The content semantics does not merge into the semantics
+                        // node 4.
+                        TestSemantics(
+                          id: 6,
+                          label: 'content',
+                          textDirection: TextDirection.ltr,
+                        ),
+                        TestSemantics(
+                          id: 7,
+                          flags: <SemanticsFlag>[SemanticsFlag.isButton,
+                            SemanticsFlag.hasEnabledState],
+                          label: 'action',
+                          textDirection: TextDirection.ltr,
+                        ),
+                      ],
+                    ),
+                  ],
+                ),
+              ],
+            ),
+          ],
+        ),
+      ],
+    ), ignoreTransform: true, ignoreId: true, ignoreRect: true));
+
+    semantics.dispose();
+  });
+
   testWidgets('AlertDialog widget always contains alert route semantics for android', (WidgetTester tester) async {
     final SemanticsTester semantics = SemanticsTester(tester);
 
@@ -1439,6 +1504,79 @@ void main() {
     semantics.dispose();
   });
 
+  // Regression test for https://github.com/flutter/flutter/issues/78229.
+  testWidgets('SimpleDialog has correct semantics for title in iOS', (WidgetTester tester) async {
+    final SemanticsTester semantics = SemanticsTester(tester);
+
+    await tester.pumpWidget(
+        MaterialApp(
+          theme: ThemeData(platform: TargetPlatform.iOS),
+          home: const SimpleDialog(
+            title: Text('title'),
+            children: <Widget>[
+              Text('content'),
+              TextButton(onPressed: null, child: Text('action'))
+            ],
+          ),
+        )
+    );
+
+    expect(semantics, hasSemantics(TestSemantics.root(
+      children: <TestSemantics>[
+        TestSemantics(
+          id: 1,
+          textDirection: TextDirection.ltr,
+          children: <TestSemantics>[
+            TestSemantics(
+              id: 2,
+              children: <TestSemantics>[
+                TestSemantics(
+                  id: 3,
+                  flags: <SemanticsFlag>[SemanticsFlag.scopesRoute],
+                  children: <TestSemantics>[
+                    TestSemantics(
+                      id: 4,
+                      children: <TestSemantics>[
+                        // Title semantics does not merge into the semantics
+                        // node 4.
+                        TestSemantics(
+                          id: 5,
+                          flags: <SemanticsFlag>[SemanticsFlag.namesRoute],
+                          label: 'title',
+                          textDirection: TextDirection.ltr,
+                        ),
+                        TestSemantics(
+                          id: 6,
+                          flags: <SemanticsFlag>[SemanticsFlag.hasImplicitScrolling],
+                          children: <TestSemantics>[
+                            TestSemantics(
+                              id: 7,
+                              label: 'content',
+                              textDirection: TextDirection.ltr,
+                            ),
+                            TestSemantics(
+                              id: 8,
+                              flags: <SemanticsFlag>[SemanticsFlag.isButton,
+                                SemanticsFlag.hasEnabledState],
+                              label: 'action',
+                              textDirection: TextDirection.ltr,
+                            ),
+                          ],
+                        ),
+                      ],
+                    ),
+                  ],
+                ),
+              ],
+            ),
+          ],
+        ),
+      ],
+    ), ignoreTransform: true, ignoreId: true, ignoreRect: true));
+
+    semantics.dispose();
+  });
+
   testWidgets('Dismissible.confirmDismiss defers to an AlertDialog', (WidgetTester tester) async {
     final GlobalKey<ScaffoldState> _scaffoldKey = GlobalKey<ScaffoldState>();
     final List<int> dismissedItems = <int>[];