diff --git a/packages/devtools_app/lib/src/shared/charts/treemap.dart b/packages/devtools_app/lib/src/shared/charts/treemap.dart
index dae9c34600e..7580a0e4036 100644
--- a/packages/devtools_app/lib/src/shared/charts/treemap.dart
+++ b/packages/devtools_app/lib/src/shared/charts/treemap.dart
@@ -401,6 +401,7 @@ class _TreemapState extends State<Treemap> {
             richMessage:
                 hoveredNode?.displayTextSpan(
                   defaultTextStyle: defaultTextStyle,
+                  color: Theme.of(context).colorScheme.tooltipTextColor,
                 ) ??
                 const TextSpan(text: ''),
             waitDuration: tooltipWaitLong,
diff --git a/packages/devtools_app/release_notes/NEXT_RELEASE_NOTES.md b/packages/devtools_app/release_notes/NEXT_RELEASE_NOTES.md
index b3097459877..669450b922b 100644
--- a/packages/devtools_app/release_notes/NEXT_RELEASE_NOTES.md
+++ b/packages/devtools_app/release_notes/NEXT_RELEASE_NOTES.md
@@ -90,7 +90,8 @@ To learn more about DevTools, check out the
 
 ## App size tool updates
 
-TODO: Remove this section if there are not any updates.
+* Fixed treemap tooltip text color across light and dark theme
+  [#10035](https://github.com/flutter/devtools/pull/10035)
 
 ## Deep links tool updates
 
diff --git a/packages/devtools_app/test/shared/charts/treemap_test.dart b/packages/devtools_app/test/shared/charts/treemap_test.dart
index f5d24be6baa..2324a985448 100644
--- a/packages/devtools_app/test/shared/charts/treemap_test.dart
+++ b/packages/devtools_app/test/shared/charts/treemap_test.dart
@@ -3,6 +3,7 @@
 // found in the LICENSE file or at https://developers.google.com/open-source/licenses/bsd.
 
 import 'dart:convert';
+import 'dart:ui';
 
 import 'package:devtools_app/src/service/service_manager.dart';
 import 'package:devtools_app/src/shared/charts/treemap.dart';
@@ -29,7 +30,11 @@ void main() {
   }
 
   // Pump treemap widget with tree built with test data.
-  Future<void> pumpTreemapWidget(WidgetTester tester, Key treemapKey) async {
+  Future<void> pumpTreemapWidget(
+    WidgetTester tester,
+    Key treemapKey, {
+    bool isDarkTheme = false,
+  }) async {
     await tester.pumpWidget(
       wrap(
         LayoutBuilder(
@@ -45,6 +50,7 @@ void main() {
             );
           },
         ),
+        isDarkTheme: isDarkTheme,
       ),
     );
     await tester.pumpAndSettle();
@@ -221,6 +227,52 @@ void main() {
       await tester.pumpAndSettle(const Duration(seconds: 2));
     }, skip: kIsWeb);
   });
+
+  group('Treemap tooltip text color', () {
+    setUp(() {
+      root = TreemapNode(name: 'root')
+        ..addChild(
+          TreemapNode(name: 'parent', byteSize: 1000)
+            ..addChild(TreemapNode(name: 'leaf_1', byteSize: 500))
+            ..addChild(TreemapNode(name: 'leaf_2', byteSize: 500)),
+        );
+    });
+    for (final isDarkTheme in [false, true]) {
+      final themeName = isDarkTheme ? 'dark' : 'light';
+      testWidgetsWithWindowSize(
+        'tooltip has correct text color in $themeName theme',
+        windowSize,
+        (WidgetTester tester) async {
+          const treemapKey = Key('Treemap');
+          await pumpTreemapWidget(tester, treemapKey, isDarkTheme: isDarkTheme);
+
+          final tooltipFinder = find.byWidgetPredicate(
+            (widget) => widget is DevToolsTooltip && widget.richMessage != null,
+          );
+          final customPaint = find.descendant(
+            of: tooltipFinder,
+            matching: find.byType(CustomPaint),
+          );
+
+          // Hover over the painted cell.
+          final gesture = await tester.createGesture(
+            kind: PointerDeviceKind.mouse,
+          );
+          await gesture.addPointer(location: Offset.zero);
+          addTearDown(gesture.removePointer);
+          await gesture.moveTo(tester.getCenter(customPaint));
+          await tester.pumpAndSettle();
+
+          final tooltip = tester.widget<DevToolsTooltip>(tooltipFinder);
+          final textSpan = tooltip.richMessage as TextSpan?;
+          final expectedColor = isDarkTheme ? Colors.black : Colors.white;
+          expect(textSpan, isNotNull);
+          expect(textSpan!.text, isNotEmpty);
+          expect(textSpan.style?.color, equals(expectedColor));
+        },
+      );
+    }
+  });
 }
 
 Future<TreemapNode> _loadSnapshotJsonAsTree(String snapshotJson) async {
diff --git a/packages/devtools_test/lib/src/helpers/wrappers.dart b/packages/devtools_test/lib/src/helpers/wrappers.dart
index 0a70c24940c..fc7f002abee 100644
--- a/packages/devtools_test/lib/src/helpers/wrappers.dart
+++ b/packages/devtools_test/lib/src/helpers/wrappers.dart
@@ -21,20 +21,32 @@ import 'package:provider/provider.dart';
 /// for widget state to be preserved.
 final _testNavigatorKey = GlobalKey<NavigatorState>();
 
+/// Returns the [ThemeData] used by [wrap] and [wrapSimple] test helper widgets.
+ThemeData _testTheme({required bool isDarkTheme}) {
+  return themeFor(
+    isDarkTheme: isDarkTheme,
+    ideTheme: IdeTheme(),
+    theme: ThemeData(
+      useMaterial3: true,
+      colorScheme: isDarkTheme ? darkColorScheme : lightColorScheme,
+    ),
+  );
+}
+
 /// Wraps [widget] with the build context it needs to load in a test as well as
 /// the [DevToolsRouterDelegate].
 ///
 /// This includes a [MaterialApp] to provide context like [Theme.of], a
 /// [Material] to support elements like [TextField] that draw ink effects, and a
 /// [Directionality] to support [RenderFlex] widgets like [Row] and [Column].
-Widget wrap(Widget widget, {DevToolsQueryParams? queryParams}) {
+Widget wrap(
+  Widget widget, {
+  DevToolsQueryParams? queryParams,
+  bool isDarkTheme = false,
+}) {
   setGlobal(GlobalKey<NavigatorState>, _testNavigatorKey);
   return MaterialApp.router(
-    theme: themeFor(
-      isDarkTheme: false,
-      ideTheme: IdeTheme(),
-      theme: ThemeData(useMaterial3: true, colorScheme: lightColorScheme),
-    ),
+    theme: _testTheme(isDarkTheme: isDarkTheme),
     routerDelegate: DevToolsRouterDelegate.test(
       (context, page, args, state) => MaterialPage(
         child: Material(
@@ -62,13 +74,9 @@ Widget wrap(Widget widget, {DevToolsQueryParams? queryParams}) {
 /// This includes a [MaterialApp] to provide context like [Theme.of], a
 /// [Material] to support elements like [TextField] that draw ink effects, and a
 /// [Directionality] to support [RenderFlex] widgets like [Row] and [Column].
-Widget wrapSimple(Widget widget) {
+Widget wrapSimple(Widget widget, {bool isDarkTheme = false}) {
   return MaterialApp(
-    theme: themeFor(
-      isDarkTheme: false,
-      ideTheme: IdeTheme(),
-      theme: ThemeData(useMaterial3: true, colorScheme: lightColorScheme),
-    ),
+    theme: _testTheme(isDarkTheme: isDarkTheme),
     home: Material(
       child: Directionality(
         textDirection: TextDirection.ltr,
@@ -99,6 +107,7 @@ Widget wrapWithControllers(
   AccessibilityController? accessibility,
   bool includeRouter = true,
   DevToolsQueryParams? queryParams,
+  bool isDarkTheme = false,
 }) {
   // The [ScreenControllers] class uses the [OfflineDataController] class to
   // determine which type of controller should be returned from
@@ -192,8 +201,8 @@ Widget wrapWithControllers(
     child = MultiProvider(providers: providers, child: child);
   }
   return includeRouter
-      ? wrap(child, queryParams: queryParams)
-      : wrapSimple(child);
+      ? wrap(child, queryParams: queryParams, isDarkTheme: isDarkTheme)
+      : wrapSimple(child, isDarkTheme: isDarkTheme);
 }
 
 Widget wrapWithNotifications(Widget child) {