diff --git a/DEPRECATIONS.md b/DEPRECATIONS.md
index 7e6cbfdb49..3cb972d569 100644
--- a/DEPRECATIONS.md
+++ b/DEPRECATIONS.md
@@ -21,6 +21,7 @@ The following is a list of deprecations, according to the [Deprecation Policy](h
 | DEPPS15 | Config option `readOnlyMasterKeyIps` defaults to `['127.0.0.1', '::1']`                      | [#10115](https://github.com/parse-community/parse-server/pull/10115)   | 9.5.0 (2026)                    | 10.0.0 (2027)                   | deprecated            | -     |
 | DEPPS16 | Remove config option `mountPlayground`                                                       | [#10110](https://github.com/parse-community/parse-server/issues/10110) | 9.5.0 (2026)                    | 10.0.0 (2027)                   | deprecated            | -     |
 | DEPPS17 | Remove config option `playgroundPath`                                                        | [#10110](https://github.com/parse-community/parse-server/issues/10110) | 9.5.0 (2026)                    | 10.0.0 (2027)                   | deprecated            | -     |
+| DEPPS18 | Config option `requestComplexity` limits enabled by default                                  | [#10207](https://github.com/parse-community/parse-server/pull/10207)   | 9.6.0 (2026)                    | 10.0.0 (2027)                   | deprecated            | -     |
 
 [i_deprecation]: ## "The version and date of the deprecation."
 [i_change]: ## "The version and date of the planned change."
diff --git a/spec/Deprecator.spec.js b/spec/Deprecator.spec.js
index 7fe925c3fc..021a56903b 100644
--- a/spec/Deprecator.spec.js
+++ b/spec/Deprecator.spec.js
@@ -149,4 +149,55 @@ describe('Deprecator', () => {
       })
     );
   });
+
+  it('logs deprecation for requestComplexity limits when not set', async () => {
+    const logSpy = spyOn(Deprecator, '_logOption').and.callFake(() => {});
+
+    await reconfigureServer();
+    const keys = [
+      'requestComplexity.includeDepth',
+      'requestComplexity.includeCount',
+      'requestComplexity.subqueryDepth',
+      'requestComplexity.queryDepth',
+      'requestComplexity.graphQLDepth',
+      'requestComplexity.graphQLFields',
+    ];
+    for (const key of keys) {
+      expect(logSpy).toHaveBeenCalledWith(
+        jasmine.objectContaining({
+          optionKey: key,
+        })
+      );
+    }
+  });
+
+  it('does not log deprecation for requestComplexity limits when explicitly set', async () => {
+    const logSpy = spyOn(Deprecator, '_logOption').and.callFake(() => {});
+
+    await reconfigureServer({
+      requestComplexity: {
+        includeDepth: 10,
+        includeCount: 100,
+        subqueryDepth: 10,
+        queryDepth: 10,
+        graphQLDepth: 20,
+        graphQLFields: 200,
+      },
+    });
+    const keys = [
+      'requestComplexity.includeDepth',
+      'requestComplexity.includeCount',
+      'requestComplexity.subqueryDepth',
+      'requestComplexity.queryDepth',
+      'requestComplexity.graphQLDepth',
+      'requestComplexity.graphQLFields',
+    ];
+    for (const key of keys) {
+      expect(logSpy).not.toHaveBeenCalledWith(
+        jasmine.objectContaining({
+          optionKey: key,
+        })
+      );
+    }
+  });
 });
diff --git a/src/Deprecator/Deprecations.js b/src/Deprecator/Deprecations.js
index 60e37e6efb..ad8f3ba805 100644
--- a/src/Deprecator/Deprecations.js
+++ b/src/Deprecator/Deprecations.js
@@ -41,4 +41,34 @@ module.exports = [
     changeNewKey: '',
     solution: "Use Parse Dashboard as GraphQL IDE or configure a third-party GraphQL client such as Apollo Sandbox, GraphiQL, or Insomnia with custom request headers.",
   },
+  {
+    optionKey: 'requestComplexity.includeDepth',
+    changeNewDefault: '10',
+    solution: "Set 'requestComplexity.includeDepth' to a positive integer appropriate for your app to limit include pointer chain depth, or to '-1' to disable.",
+  },
+  {
+    optionKey: 'requestComplexity.includeCount',
+    changeNewDefault: '100',
+    solution: "Set 'requestComplexity.includeCount' to a positive integer appropriate for your app to limit the number of include paths per query, or to '-1' to disable.",
+  },
+  {
+    optionKey: 'requestComplexity.subqueryDepth',
+    changeNewDefault: '10',
+    solution: "Set 'requestComplexity.subqueryDepth' to a positive integer appropriate for your app to limit subquery nesting depth, or to '-1' to disable.",
+  },
+  {
+    optionKey: 'requestComplexity.queryDepth',
+    changeNewDefault: '10',
+    solution: "Set 'requestComplexity.queryDepth' to a positive integer appropriate for your app to limit query condition nesting depth, or to '-1' to disable.",
+  },
+  {
+    optionKey: 'requestComplexity.graphQLDepth',
+    changeNewDefault: '20',
+    solution: "Set 'requestComplexity.graphQLDepth' to a positive integer appropriate for your app to limit GraphQL field selection depth, or to '-1' to disable.",
+  },
+  {
+    optionKey: 'requestComplexity.graphQLFields',
+    changeNewDefault: '200',
+    solution: "Set 'requestComplexity.graphQLFields' to a positive integer appropriate for your app to limit the number of GraphQL field selections, or to '-1' to disable.",
+  },
 ];