diff --git a/.chronus/changes/specs_arm-multi-service-2025-11-18-17-31-26.md b/.chronus/changes/specs_arm-multi-service-2025-11-18-17-31-26.md
new file mode 100644
index 0000000000..77f6fcb406
--- /dev/null
+++ b/.chronus/changes/specs_arm-multi-service-2025-11-18-17-31-26.md
@@ -0,0 +1,7 @@
+---
+changeKind: feature
+packages:
+  - "@azure-tools/azure-http-specs"
+---
+
+Add ARM multiple services test case.
\ No newline at end of file
diff --git a/packages/azure-http-specs/spec-summary.md b/packages/azure-http-specs/spec-summary.md
index aeaaf8e3d9..9e2475c640 100644
--- a/packages/azure-http-specs/spec-summary.md
+++ b/packages/azure-http-specs/spec-summary.md
@@ -1990,6 +1990,118 @@ Expected response body:
 }
 ```
 
+### Azure_ResourceManager_MultiService_Compute_VirtualMachines_createOrUpdate
+
+- Endpoint: `put https://management.azure.com`
+
+Test that a client can expose operations from multiple services. This operaton should be called like this: `client.virtualMachines.createOrUpdate(...)`.
+
+PUT (create or update) a Virtual Machine.
+Expected path: /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/virtualMachines/vm1
+Expected query parameter: api-version=2025-04-01
+Expected request body:
+
+```json
+{
+  "location": "eastus",
+  "properties": {}
+}
+```
+
+Expected response body:
+
+```json
+{
+  "id": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/virtualMachines/vm1",
+  "name": "vm1",
+  "type": "Microsoft.Compute/virtualMachines",
+  "location": "eastus",
+  "properties": {
+    "provisioningState": "Succeeded"
+  }
+}
+```
+
+### Azure_ResourceManager_MultiService_Compute_VirtualMachines_get
+
+- Endpoint: `get https://management.azure.com`
+
+Test that a client can expose operations from multiple services. This operaton should be called like this: `client.virtualMachines.get(...)`.
+
+GET a Virtual Machine.
+Expected path: /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/virtualMachines/vm1
+Expected query parameter: api-version=2025-04-01
+
+Expected response body:
+
+```json
+{
+  "id": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/virtualMachines/vm1",
+  "name": "vm1",
+  "type": "Microsoft.Compute/virtualMachines",
+  "location": "eastus",
+  "properties": {
+    "provisioningState": "Succeeded"
+  }
+}
+```
+
+### Azure_ResourceManager_MultiService_ComputeDisk_Disks_createOrUpdate
+
+- Endpoint: `put https://management.azure.com`
+
+Test that a client can expose operations from multiple services. This operaton should be called like this: `client.disks.createOrUpdate(...)`.
+
+PUT (create or update) a Disk resource.
+Expected path: /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/disks/disk1
+Expected query parameter: api-version=2025-01-02
+Expected request body:
+
+```json
+{
+  "location": "eastus",
+  "properties": {}
+}
+```
+
+Expected response body:
+
+```json
+{
+  "id": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/disks/disk1",
+  "name": "disk1",
+  "type": "Microsoft.Compute/disks",
+  "location": "eastus",
+  "properties": {
+    "provisioningState": "Succeeded"
+  }
+}
+```
+
+### Azure_ResourceManager_MultiService_ComputeDisk_Disks_get
+
+- Endpoint: `get https://management.azure.com`
+
+Test that a client can expose operations from multiple services. This operaton should be called like this: `client.disks.get(...)`.
+
+GET a Disk resource.
+Expected path: /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/disks/disk1
+Expected query parameter: api-version=2025-01-02
+
+Expected response body:
+
+```json
+{
+  "id": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/disks/disk1",
+  "name": "disk1",
+  "type": "Microsoft.Compute/disks",
+  "location": "eastus",
+  "properties": {
+    "provisioningState": "Succeeded"
+  }
+}
+```
+
 ### Azure_ResourceManager_NonResource_NonResourceOperations_create
 
 - Endpoint: `put https://management.azure.com/subscriptions/{subscriptionId}/providers/Microsoft.NonResource/locations/{location}/otherParameters/{parameter}`
diff --git a/packages/azure-http-specs/specs/azure/resource-manager/multi-service/client.tsp b/packages/azure-http-specs/specs/azure/resource-manager/multi-service/client.tsp
new file mode 100644
index 0000000000..7dbee9a681
--- /dev/null
+++ b/packages/azure-http-specs/specs/azure/resource-manager/multi-service/client.tsp
@@ -0,0 +1,16 @@
+import "./service1.tsp";
+import "./service2.tsp";
+import "@azure-tools/typespec-client-generator-core";
+
+using Versioning;
+using Azure.Core;
+using Azure.ResourceManager;
+using Azure.ClientGenerator.Core;
+
+@client({
+  service: [
+    Azure.ResourceManager.MultiService.Compute,
+    Azure.ResourceManager.MultiService.ComputeDisk
+  ],
+})
+namespace Azure.ResourceManager.MultiService.Combined;
diff --git a/packages/azure-http-specs/specs/azure/resource-manager/multi-service/mockapi.ts b/packages/azure-http-specs/specs/azure/resource-manager/multi-service/mockapi.ts
new file mode 100644
index 0000000000..a7098899dd
--- /dev/null
+++ b/packages/azure-http-specs/specs/azure/resource-manager/multi-service/mockapi.ts
@@ -0,0 +1,111 @@
+import { json, passOnSuccess, ScenarioMockApi } from "@typespec/spec-api";
+
+export const Scenarios: Record<string, ScenarioMockApi> = {};
+
+// Mock data for Compute (VirtualMachine)
+const SUBSCRIPTION_ID = "00000000-0000-0000-0000-000000000000";
+const RESOURCE_GROUP = "test-rg";
+const LOCATION = "eastus";
+
+const virtualMachine = {
+  id: `/subscriptions/${SUBSCRIPTION_ID}/resourceGroups/${RESOURCE_GROUP}/providers/Microsoft.Compute/virtualMachines/vm1`,
+  name: "vm1",
+  type: "Microsoft.Compute/virtualMachines",
+  location: LOCATION,
+  properties: {
+    provisioningState: "Succeeded",
+  },
+};
+
+// Mock data for ComputeDisk (Disk)
+const disk = {
+  id: `/subscriptions/${SUBSCRIPTION_ID}/resourceGroups/${RESOURCE_GROUP}/providers/Microsoft.Compute/disks/disk1`,
+  name: "disk1",
+  type: "Microsoft.Compute/disks",
+  location: LOCATION,
+  properties: {
+    provisioningState: "Succeeded",
+  },
+};
+
+// Scenario: Get Virtual Machine
+Scenarios.Azure_ResourceManager_MultiService_Compute_VirtualMachines_get = passOnSuccess([
+  {
+    uri: `/subscriptions/${SUBSCRIPTION_ID}/resourceGroups/${RESOURCE_GROUP}/providers/Microsoft.Compute/virtualMachines/vm1`,
+    method: "get",
+    request: {
+      query: {
+        "api-version": "2025-04-01",
+      },
+    },
+    response: {
+      status: 200,
+      body: json(virtualMachine),
+    },
+    kind: "MockApiDefinition",
+  },
+]);
+
+// Scenario: Create or Update Virtual Machine
+Scenarios.Azure_ResourceManager_MultiService_Compute_VirtualMachines_createOrUpdate = passOnSuccess(
+  [
+    {
+      uri: `/subscriptions/${SUBSCRIPTION_ID}/resourceGroups/${RESOURCE_GROUP}/providers/Microsoft.Compute/virtualMachines/vm1`,
+      method: "put",
+      request: {
+        query: {
+          "api-version": "2025-04-01",
+        },
+        body: json({
+          location: LOCATION,
+          properties: {},
+        }),
+      },
+      response: {
+        status: 200,
+        body: json(virtualMachine),
+      },
+      kind: "MockApiDefinition",
+    },
+  ],
+);
+
+// Scenario: Get Disk
+Scenarios.Azure_ResourceManager_MultiService_ComputeDisk_Disks_get = passOnSuccess([
+  {
+    uri: `/subscriptions/${SUBSCRIPTION_ID}/resourceGroups/${RESOURCE_GROUP}/providers/Microsoft.Compute/disks/disk1`,
+    method: "get",
+    request: {
+      query: {
+        "api-version": "2025-01-02",
+      },
+    },
+    response: {
+      status: 200,
+      body: json(disk),
+    },
+    kind: "MockApiDefinition",
+  },
+]);
+
+// Scenario: Create or Update Disk
+Scenarios.Azure_ResourceManager_MultiService_ComputeDisk_Disks_createOrUpdate = passOnSuccess([
+  {
+    uri: `/subscriptions/${SUBSCRIPTION_ID}/resourceGroups/${RESOURCE_GROUP}/providers/Microsoft.Compute/disks/disk1`,
+    method: "put",
+    request: {
+      query: {
+        "api-version": "2025-01-02",
+      },
+      body: json({
+        location: LOCATION,
+        properties: {},
+      }),
+    },
+    response: {
+      status: 200,
+      body: json(disk),
+    },
+    kind: "MockApiDefinition",
+  },
+]);
diff --git a/packages/azure-http-specs/specs/azure/resource-manager/multi-service/service1.tsp b/packages/azure-http-specs/specs/azure/resource-manager/multi-service/service1.tsp
new file mode 100644
index 0000000000..131c840b38
--- /dev/null
+++ b/packages/azure-http-specs/specs/azure/resource-manager/multi-service/service1.tsp
@@ -0,0 +1,109 @@
+import "@typespec/versioning";
+import "@azure-tools/typespec-azure-resource-manager";
+import "@typespec/spector";
+
+using TypeSpec.Versioning;
+using Spector;
+
+/**
+ * Compute Client
+ */
+@armProviderNamespace("Microsoft.Compute")
+@service(#{ title: "Azure Compute resource management API." })
+@versioned(Versions)
+namespace Azure.ResourceManager.MultiService.Compute;
+
+/**
+ * The available API versions.
+ */
+enum Versions {
+  /**
+   * The 2024-11-01 API version.
+   */
+  @armCommonTypesVersion(Azure.ResourceManager.CommonTypes.Versions.v3)
+  v2024_11_01: "2024-11-01",
+
+  /**
+   * The 2025-04-01 API version.
+   */
+  @armCommonTypesVersion(Azure.ResourceManager.CommonTypes.Versions.v3)
+  v2025_04_01: "2025-04-01",
+}
+
+/**
+ * Describes a Virtual Machine.
+ */
+model VirtualMachine is Azure.ResourceManager.TrackedResource<VirtualMachineProperties> {
+  ...ResourceNameParameter<
+    Resource = VirtualMachine,
+    KeyName = "vmName",
+    SegmentName = "virtualMachines",
+    NamePattern = ""
+  >;
+}
+
+model VirtualMachineProperties {
+  @visibility(Lifecycle.Read)
+  provisioningState?: ResourceProvisioningState;
+}
+
+@armResourceOperations
+interface VirtualMachines {
+  /**
+   * Retrieves information about the model view or the instance view of a virtual machine.
+   */
+  @scenario
+  @scenarioDoc("""
+    Test that a client can expose operations from multiple services. This operaton should be called like this: `client.virtualMachines.get(...)`.
+    
+    GET a Virtual Machine.
+    Expected path: /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/virtualMachines/vm1
+    Expected query parameter: api-version=2025-04-01
+    
+    Expected response body:
+    ```json
+    {
+      "id": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/virtualMachines/vm1",
+      "name": "vm1",
+      "type": "Microsoft.Compute/virtualMachines",
+      "location": "eastus",
+      "properties": {
+        "provisioningState": "Succeeded"
+      }
+    }
+    ```
+    """)
+  get is ArmResourceRead<VirtualMachine>;
+
+  /**
+   * The operation to create or update a virtual machine. Please note some properties can be set only during virtual machine creation.
+   */
+  @scenario
+  @scenarioDoc("""
+    Test that a client can expose operations from multiple services. This operaton should be called like this: `client.virtualMachines.createOrUpdate(...)`.
+    
+    PUT (create or update) a Virtual Machine.
+    Expected path: /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/virtualMachines/vm1
+    Expected query parameter: api-version=2025-04-01
+    Expected request body:
+    ```json
+    {
+      "location": "eastus",
+      "properties": {}
+    }
+    ```
+    Expected response body:
+    ```json
+    {
+      "id": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/virtualMachines/vm1",
+      "name": "vm1",
+      "type": "Microsoft.Compute/virtualMachines",
+      "location": "eastus",
+      "properties": {
+        "provisioningState": "Succeeded"
+      }
+    }
+    ```
+    """)
+  createOrUpdate is ArmResourceCreateOrUpdateAsync<VirtualMachine>;
+}
diff --git a/packages/azure-http-specs/specs/azure/resource-manager/multi-service/service2.tsp b/packages/azure-http-specs/specs/azure/resource-manager/multi-service/service2.tsp
new file mode 100644
index 0000000000..528b78779d
--- /dev/null
+++ b/packages/azure-http-specs/specs/azure/resource-manager/multi-service/service2.tsp
@@ -0,0 +1,112 @@
+import "@typespec/versioning";
+import "@azure-tools/typespec-azure-resource-manager";
+import "@typespec/spector";
+
+using TypeSpec.Versioning;
+using Spector;
+
+/**
+ * Compute Client
+ */
+@armProviderNamespace("Microsoft.Compute")
+@service(#{ title: "Azure Compute resource management API." })
+@versioned(Versions)
+namespace Azure.ResourceManager.MultiService.ComputeDisk;
+
+/**
+ * The available API versions.
+ */
+enum Versions {
+  /**
+   * The 2024-03-02 API version.
+   */
+  @armCommonTypesVersion(Azure.ResourceManager.CommonTypes.Versions.v3)
+  v2024_03_02: "2024-03-02",
+
+  /**
+   * The 2025-01-02 API version.
+   */
+  @armCommonTypesVersion(Azure.ResourceManager.CommonTypes.Versions.v3)
+  v2025_01_02: "2025-01-02",
+}
+
+/**
+ * Disk resource.
+ */
+model Disk is Azure.ResourceManager.TrackedResource<DiskProperties> {
+  ...ResourceNameParameter<
+    Resource = Disk,
+    KeyName = "diskName",
+    SegmentName = "disks",
+    NamePattern = ""
+  >;
+}
+
+/**
+ * Disk resource properties.
+ */
+model DiskProperties {
+  @visibility(Lifecycle.Read)
+  provisioningState?: ResourceProvisioningState;
+}
+
+@armResourceOperations
+interface Disks {
+  /**
+   * Gets information about a disk.
+   */
+  @scenario
+  @scenarioDoc("""
+    Test that a client can expose operations from multiple services. This operaton should be called like this: `client.disks.get(...)`.
+    
+    GET a Disk resource.
+    Expected path: /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/disks/disk1
+    Expected query parameter: api-version=2025-01-02
+    
+    Expected response body:
+    ```json
+    {
+      "id": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/disks/disk1",
+      "name": "disk1",
+      "type": "Microsoft.Compute/disks",
+      "location": "eastus",
+      "properties": {
+        "provisioningState": "Succeeded"
+      }
+    }
+    ```
+    """)
+  get is ArmResourceRead<Disk>;
+
+  /**
+   * Creates or updates a disk.
+   */
+  @scenario
+  @scenarioDoc("""
+    Test that a client can expose operations from multiple services. This operaton should be called like this: `client.disks.createOrUpdate(...)`.
+    
+    PUT (create or update) a Disk resource.
+    Expected path: /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/disks/disk1
+    Expected query parameter: api-version=2025-01-02
+    Expected request body:
+    ```json
+    {
+      "location": "eastus",
+      "properties": {}
+    }
+    ```
+    Expected response body:
+    ```json
+    {
+      "id": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/test-rg/providers/Microsoft.Compute/disks/disk1",
+      "name": "disk1",
+      "type": "Microsoft.Compute/disks",
+      "location": "eastus",
+      "properties": {
+        "provisioningState": "Succeeded"
+      }
+    }
+    ```
+    """)
+  createOrUpdate is ArmResourceCreateOrUpdateAsync<Disk>;
+}