diff --git a/packages/reactivity/src/reactive.ts b/packages/reactivity/src/reactive.ts
index 40edf1c8e3b..935b2deead5 100644
--- a/packages/reactivity/src/reactive.ts
+++ b/packages/reactivity/src/reactive.ts
@@ -140,8 +140,15 @@ export function shallowReactive<T extends object>(
   )
 }
 
-type Primitive = string | number | boolean | bigint | symbol | undefined | null
-export type Builtin = Primitive | Function | Date | Error | RegExp
+export type Primitive =
+  | string
+  | number
+  | boolean
+  | bigint
+  | symbol
+  | undefined
+  | null
+export type Builtin = Function | Date | Error | RegExp
 export type DeepReadonly<T> = T extends Builtin
   ? T
   : T extends Map<infer K, infer V>
diff --git a/packages/reactivity/src/ref.ts b/packages/reactivity/src/ref.ts
index 92d0b6751b4..7a1c64eb9f7 100644
--- a/packages/reactivity/src/ref.ts
+++ b/packages/reactivity/src/ref.ts
@@ -16,7 +16,7 @@ import {
   isReadonly,
   isShallow
 } from './reactive'
-import type { Builtin, ShallowReactiveMarker } from './reactive'
+import type { Builtin, Primitive, ShallowReactiveMarker } from './reactive'
 import { createDep, Dep } from './dep'
 
 declare const RefSymbol: unique symbol
@@ -484,6 +484,7 @@ export type UnwrapRef<T> = T extends ShallowRef<infer V>
     : UnwrapRefSimple<T>
 
 export type UnwrapRefSimple<T> = T extends
+  | Primitive
   | Builtin
   | Ref
   | RefUnwrapBailTypes[keyof RefUnwrapBailTypes]