diff --git a/CHANGELOG.md b/CHANGELOG.md
index 57d1e503ed..92943a9e33 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -20,6 +20,7 @@
 - **feat(oauth):** import a ChatGPT/Codex connection from a raw access token (no refresh token required). (thanks @ryanngit)
 - **feat(providers):** add NVIDIA NIM image generation (FLUX models). (thanks @eng2007)
 - **feat(providers):** add Augment (Auggie CLI) as a local no-auth provider. (thanks @chamdanilukman)
+- **feat(providers):** add ModelScope as an OpenAI-compatible (API-key) provider. (thanks @tn5052)
 
 ### 🔧 Bug Fixes
 
diff --git a/open-sse/config/providers/index.ts b/open-sse/config/providers/index.ts
index a3e30f42c7..32850c900f 100644
--- a/open-sse/config/providers/index.ts
+++ b/open-sse/config/providers/index.ts
@@ -79,6 +79,7 @@ import { leonardoProvider } from "./registry/leonardo/index.ts";
 import { grok_webProvider } from "./registry/grok-web/index.ts";
 import { kieProvider } from "./registry/kie/index.ts";
 import { monsterapiProvider } from "./registry/monsterapi/index.ts";
+import { modelscopeProvider } from "./registry/modelscope/index.ts";
 import { sensenovaProvider } from "./registry/sensenova/index.ts";
 import { hyperbolicProvider } from "./registry/hyperbolic/index.ts";
 import { lambda_aiProvider } from "./registry/lambda-ai/index.ts";
@@ -252,6 +253,7 @@ export const REGISTRY: Record<string, RegistryEntry> = {
   "grok-web": grok_webProvider,
   kie: kieProvider,
   monsterapi: monsterapiProvider,
+  modelscope: modelscopeProvider,
   sensenova: sensenovaProvider,
   hyperbolic: hyperbolicProvider,
   "lambda-ai": lambda_aiProvider,
diff --git a/open-sse/config/providers/registry/modelscope/index.ts b/open-sse/config/providers/registry/modelscope/index.ts
new file mode 100644
index 0000000000..f82b7cbe72
--- /dev/null
+++ b/open-sse/config/providers/registry/modelscope/index.ts
@@ -0,0 +1,24 @@
+import type { RegistryEntry } from "../../shared.ts";
+
+// ModelScope (Alibaba 魔搭) — OpenAI-compatible API-Inference, ported from upstream
+// 9router PR #1764 (@tn5052). The upstream PR hardcoded `https://api-inference.modelscope.ai/...`
+// (`.ai` TLD) and a static 5-model list. Both were dropped here after verification:
+//
+// - baseUrl: ModelScope's own API-Inference docs (modelscope.cn/docs/model-service/API-Inference)
+//   and third-party integration guides (e.g. Alibaba Cloud Model Studio compatibility docs)
+//   consistently confirm the production domain is `api-inference.modelscope.cn` — the `.cn` TLD,
+//   not `.ai`. Using the unverified `.ai` domain would have shipped a broken provider.
+// - models: passthrough + empty static seed instead of copying the PR's 5-model snapshot, since
+//   ModelScope hosts a large and fast-moving open-model catalog — `modelsUrl` keeps the list live.
+export const modelscopeProvider: RegistryEntry = {
+  id: "modelscope",
+  alias: "ms",
+  format: "openai",
+  executor: "default",
+  baseUrl: "https://api-inference.modelscope.cn/v1/chat/completions",
+  modelsUrl: "https://api-inference.modelscope.cn/v1/models",
+  authType: "apikey",
+  authHeader: "bearer",
+  passthroughModels: true,
+  models: [],
+};
diff --git a/src/shared/constants/providers/apikey/inference-hosts.ts b/src/shared/constants/providers/apikey/inference-hosts.ts
index f019501590..a0f00fae36 100644
--- a/src/shared/constants/providers/apikey/inference-hosts.ts
+++ b/src/shared/constants/providers/apikey/inference-hosts.ts
@@ -265,6 +265,21 @@ export const APIKEY_PROVIDERS_INFERENCE = {
     passthroughModels: true,
     authHint: "Get API key at monsterapi.ai",
   },
+  modelscope: {
+    id: "modelscope",
+    alias: "ms",
+    name: "ModelScope",
+    icon: "cloud",
+    color: "#FF6A00",
+    textIcon: "MS",
+    website: "https://modelscope.cn",
+    hasFree: true,
+    // #1764 (upstream 9router): OpenAI-compatible API-Inference. Base URL verified
+    // live against ModelScope's own docs — the upstream PR used the `.ai` TLD, but
+    // the confirmed production domain is `api-inference.modelscope.cn` (see registry
+    // entry + test guard).
+    freeNote: "Free tier via ModelScope API-Inference — Alibaba account required.",
+  },
   byteplus: {
     id: "byteplus",
     alias: "bpm",
diff --git a/tests/snapshots/provider/translate-path.json b/tests/snapshots/provider/translate-path.json
index b535763f8a..312c66b7b9 100644
--- a/tests/snapshots/provider/translate-path.json
+++ b/tests/snapshots/provider/translate-path.json
@@ -2709,6 +2709,29 @@
       "stream": "https://api.modal.ai/v1/chat/completions"
     }
   },
+  "modelscope": {
+    "format": "openai",
+    "headers": {
+      "apiKey": {
+        "Accept": "text/event-stream",
+        "Authorization": "Bearer <TOK>",
+        "Content-Type": "application/json"
+      },
+      "nonStream": {
+        "Authorization": "Bearer <TOK>",
+        "Content-Type": "application/json"
+      },
+      "oauth": {
+        "Accept": "text/event-stream",
+        "Authorization": "Bearer <TOK>",
+        "Content-Type": "application/json"
+      }
+    },
+    "url": {
+      "nonStream": "https://api-inference.modelscope.cn/v1/chat/completions",
+      "stream": "https://api-inference.modelscope.cn/v1/chat/completions"
+    }
+  },
   "monsterapi": {
     "format": "openai",
     "headers": {
diff --git a/tests/unit/modelscope-provider.test.ts b/tests/unit/modelscope-provider.test.ts
new file mode 100644
index 0000000000..c4bdbfce73
--- /dev/null
+++ b/tests/unit/modelscope-provider.test.ts
@@ -0,0 +1,65 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+
+import { modelscopeProvider } from "../../open-sse/config/providers/registry/modelscope/index.ts";
+import { REGISTRY } from "../../open-sse/config/providerRegistry.ts";
+import { APIKEY_PROVIDERS } from "../../src/shared/constants/providers/apikey/index.ts";
+import { AI_PROVIDERS, getProviderById } from "../../src/shared/constants/providers.ts";
+
+// Upstream 9router PR #1764 (@tn5052) ports ModelScope (Alibaba 魔搭) as an OpenAI-compatible
+// BYOK free-tier provider. The upstream PR hardcoded `https://api-inference.modelscope.ai/...`
+// (`.ai` TLD) — ModelScope's own docs confirm the real production domain is
+// `api-inference.modelscope.cn` (`.cn` TLD). This suite locks in the verified domain and
+// guards against a regression back to the unverified `.ai` domain.
+
+test("providers-shape: modelscope is registered in APIKEY_PROVIDERS metadata", () => {
+  assert.ok("modelscope" in APIKEY_PROVIDERS, "modelscope missing from APIKEY_PROVIDERS");
+  const meta = (APIKEY_PROVIDERS as Record<string, Record<string, unknown>>).modelscope;
+  assert.equal(meta.id, "modelscope");
+  assert.equal(meta.alias, "ms");
+  assert.equal(meta.name, "ModelScope");
+  assert.equal(meta.website, "https://modelscope.cn");
+  assert.equal(meta.hasFree, true);
+});
+
+test("providers-shape: modelscope is a canonical AI_PROVIDERS entry resolvable by id", () => {
+  assert.ok("modelscope" in AI_PROVIDERS, "modelscope missing from AI_PROVIDERS");
+  const provider = getProviderById("modelscope");
+  assert.ok(provider, "getProviderById('modelscope') returned nothing");
+  assert.equal(provider?.id, "modelscope");
+});
+
+test("registry resolution: modelscope resolves in the provider REGISTRY as OpenAI-compatible", () => {
+  assert.ok("modelscope" in REGISTRY, "modelscope missing from REGISTRY");
+  const entry = REGISTRY.modelscope;
+  assert.equal(entry.format, "openai");
+  assert.equal(entry.executor, "default");
+  assert.equal(entry.authType, "apikey");
+  assert.equal(entry.authHeader, "bearer");
+  assert.equal(entry, modelscopeProvider);
+});
+
+test("registry resolution: modelscope uses passthrough models with an empty static seed list", () => {
+  assert.equal(modelscopeProvider.passthroughModels, true);
+  assert.deepEqual(modelscopeProvider.models, []);
+  assert.equal(
+    modelscopeProvider.modelsUrl,
+    "https://api-inference.modelscope.cn/v1/models",
+    "modelsUrl must point at the verified .cn domain"
+  );
+});
+
+test("baseUrl guard: modelscope targets the verified api-inference.modelscope.cn domain (not .ai)", () => {
+  assert.equal(
+    modelscopeProvider.baseUrl,
+    "https://api-inference.modelscope.cn/v1/chat/completions"
+  );
+  assert.ok(
+    modelscopeProvider.baseUrl.includes("api-inference.modelscope.cn"),
+    `baseUrl must use the verified .cn domain, got: ${modelscopeProvider.baseUrl}`
+  );
+  assert.ok(
+    !modelscopeProvider.baseUrl.includes("modelscope.ai"),
+    "baseUrl must not regress to the upstream PR's unverified .ai domain"
+  );
+});
diff --git a/tests/unit/providers-constants-split.test.ts b/tests/unit/providers-constants-split.test.ts
index 601d03f72e..25ad085af1 100644
--- a/tests/unit/providers-constants-split.test.ts
+++ b/tests/unit/providers-constants-split.test.ts
@@ -1,7 +1,7 @@
 // Characterization of the providers.ts catalog split (god-file decomposition): the host became a
 // barrel that re-exports 10 data catalogs now living under constants/providers/*, and APIKEY is
 // merged from 6 semantic family files (apikey/<family>.ts). Locks: the public surface (every catalog
-// + helpers still exported), the spread-merge integrity (159 APIKEY entries, no loss/dup), and that
+// + helpers still exported), the spread-merge integrity (160 APIKEY entries, no loss/dup), and that
 // load-time Zod validation still runs. Pure-data move → behavior must be identical.
 import { test } from "node:test";
 import assert from "node:assert/strict";
@@ -31,12 +31,12 @@ test("barrel still exports every catalog + key helpers", () => {
   }
 });
 
-test("APIKEY_PROVIDERS merges the 6 family files into 159 entries (no loss / no dup)", async () => {
+test("APIKEY_PROVIDERS merges the 6 family files into 160 entries (no loss / no dup)", async () => {
   const keys = Object.keys((P as Record<string, object>).APIKEY_PROVIDERS);
-  assert.equal(keys.length, 159);
-  assert.equal(new Set(keys).size, 159, "duplicate keys after spread-merge");
+  assert.equal(keys.length, 160);
+  assert.equal(new Set(keys).size, 160, "duplicate keys after spread-merge");
   // the merged object's entry-count equals the sum of the 6 semantic family files; families are a
-  // strict partition (every provider in exactly one), so the sum must be exactly 159.
+  // strict partition (every provider in exactly one), so the sum must be exactly 160.
   const families: [string, string][] = [
     ["gateways", "APIKEY_PROVIDERS_GATEWAYS"],
     ["frontier-labs", "APIKEY_PROVIDERS_FRONTIER"],
@@ -56,7 +56,7 @@ test("APIKEY_PROVIDERS merges the 6 family files into 159 entries (no loss / no
       seen.add(k);
     }
   }
-  assert.equal(famTotal, 159, "families must partition all 159 providers");
+  assert.equal(famTotal, 160, "families must partition all 160 providers");
 });
 
 test("AI_PROVIDERS Proxy aggregates all sections; lookups resolve", () => {