diff --git a/.changeset/lemon-donuts-clap.md b/.changeset/lemon-donuts-clap.md
new file mode 100644
index 0000000000..75408d2584
--- /dev/null
+++ b/.changeset/lemon-donuts-clap.md
@@ -0,0 +1,5 @@
+---
+'@backstage/backend-plugin-api': patch
+---
+
+Ensure that root scoped services cannot accept (at a type level) plugin scoped deps
diff --git a/packages/backend-app-api/src/wiring/ServiceRegistry.test.ts b/packages/backend-app-api/src/wiring/ServiceRegistry.test.ts
index 18e2ac4398..32807ca826 100644
--- a/packages/backend-app-api/src/wiring/ServiceRegistry.test.ts
+++ b/packages/backend-app-api/src/wiring/ServiceRegistry.test.ts
@@ -125,6 +125,7 @@ describe('ServiceRegistry', () => {
 
   it('should not be possible for root scoped services to depend on plugin scoped services', async () => {
     const factory = createServiceFactory({
+      // @ts-expect-error
       service: ref2,
       deps: { pluginDep: ref1 },
       async factory() {
diff --git a/packages/backend-plugin-api/api-report.md b/packages/backend-plugin-api/api-report.md
index 17cc521499..7807dd96c6 100644
--- a/packages/backend-plugin-api/api-report.md
+++ b/packages/backend-plugin-api/api-report.md
@@ -138,7 +138,7 @@ export function createServiceFactory<
   TService,
   TImpl extends TService,
   TDeps extends {
-    [name in string]: ServiceRef<unknown>;
+    [name in string]: ServiceRef<unknown, 'root'>;
   },
   TOpts extends object | undefined = undefined,
 >(
@@ -150,7 +150,7 @@ export function createServiceFactory<
   TService,
   TImpl extends TService,
   TDeps extends {
-    [name in string]: ServiceRef<unknown>;
+    [name in string]: ServiceRef<unknown, 'root'>;
   },
   TOpts extends object | undefined = undefined,
 >(
diff --git a/packages/backend-plugin-api/src/services/system/types.test.ts b/packages/backend-plugin-api/src/services/system/types.test.ts
index 4d0432505e..adf097761b 100644
--- a/packages/backend-plugin-api/src/services/system/types.test.ts
+++ b/packages/backend-plugin-api/src/services/system/types.test.ts
@@ -166,7 +166,6 @@ describe('createServiceFactory', () => {
       service: createServiceRef({ id: 'foo', scope: 'root' }),
       deps: {
         root: rootDep,
-        plugin: pluginDep,
       },
       async factory({ root }) {
         const root1: number = root;
@@ -192,7 +191,6 @@ describe('createServiceFactory', () => {
       service: createServiceRef({ id: 'foo', scope: 'root' }),
       deps: {
         root: rootDep,
-        plugin: pluginDep,
       },
       async factory({ root }) {
         const root1: number = root;
diff --git a/packages/backend-plugin-api/src/services/system/types.ts b/packages/backend-plugin-api/src/services/system/types.ts
index b8fb12fe44..329502369e 100644
--- a/packages/backend-plugin-api/src/services/system/types.ts
+++ b/packages/backend-plugin-api/src/services/system/types.ts
@@ -172,7 +172,7 @@ export interface PluginServiceFactoryConfig<
 export function createServiceFactory<
   TService,
   TImpl extends TService,
-  TDeps extends { [name in string]: ServiceRef<unknown> },
+  TDeps extends { [name in string]: ServiceRef<unknown, 'root'> },
   TOpts extends object | undefined = undefined,
 >(
   config: RootServiceFactoryConfig<TService, TImpl, TDeps>,
@@ -186,7 +186,7 @@ export function createServiceFactory<
 export function createServiceFactory<
   TService,
   TImpl extends TService,
-  TDeps extends { [name in string]: ServiceRef<unknown> },
+  TDeps extends { [name in string]: ServiceRef<unknown, 'root'> },
   TOpts extends object | undefined = undefined,
 >(
   config: (options?: TOpts) => RootServiceFactoryConfig<TService, TImpl, TDeps>,