diff --git a/.changeset/polite-meals-drop.md b/.changeset/polite-meals-drop.md
new file mode 100644
index 000000000..90471514e
--- /dev/null
+++ b/.changeset/polite-meals-drop.md
@@ -0,0 +1,5 @@
+---
+"mobx-react": minor
+---
+
+Make mobx-react compatible with TS 4.8+
diff --git a/packages/mobx-react/__tests__/context.test.tsx b/packages/mobx-react/__tests__/context.test.tsx
index 5a0ae7fb2..e88dbda85 100644
--- a/packages/mobx-react/__tests__/context.test.tsx
+++ b/packages/mobx-react/__tests__/context.test.tsx
@@ -71,7 +71,7 @@ test("getDerivedStateFromProps works #447", () => {
         }
     }
 
-    const MainInjected = inject(({ store }) => ({ thing: store.thing }))(Main)
+    const MainInjected = inject(({ store }: { store: { thing: number } }) => ({ thing: store.thing }))(Main)
 
     const store = { thing: 3 }
 
diff --git a/packages/mobx-react/__tests__/observer.test.tsx b/packages/mobx-react/__tests__/observer.test.tsx
index e7c995267..b4b0285d3 100644
--- a/packages/mobx-react/__tests__/observer.test.tsx
+++ b/packages/mobx-react/__tests__/observer.test.tsx
@@ -326,7 +326,7 @@ test("observer component can be injected", () => {
     )
 
     // N.B, the injected component will be observer since mobx-react 4.0!
-    inject(() => {})(
+    inject(() => ({}))(
         observer(
             class T extends React.Component {
                 render() {
diff --git a/packages/mobx-react/src/inject.ts b/packages/mobx-react/src/inject.ts
index d46977998..88e0f3341 100644
--- a/packages/mobx-react/src/inject.ts
+++ b/packages/mobx-react/src/inject.ts
@@ -80,7 +80,7 @@ export function inject(
 ): <T extends IReactComponent<any>>(
     target: T
 ) => T & (T extends IReactComponent<infer P> ? IWrappedComponent<P> : never)
-export function inject<S, P, I, C>(
+export function inject<S extends IValueMap = {}, P extends IValueMap = {}, I extends IValueMap = {}, C extends IValueMap = {}>(
     fn: IStoresToProps<S, P, I, C>
 ): <T extends IReactComponent>(target: T) => T & IWrappedComponent<P>