diff --git a/react-day-picker/index.d.ts b/react-day-picker/index.d.ts
index f2993d95c5..01c5492922 100644
--- a/react-day-picker/index.d.ts
+++ b/react-day-picker/index.d.ts
@@ -75,7 +75,7 @@ declare namespace ReactDayPicker {
         toMonth?: Date;
         localeUtils?: LocaleUtils;
         locale?: string;
-        captionElement?: React.ReactElement<CaptionElementProps> | null;
+        captionElement?: React.ReactElement<CaptionElementProps>;
         onDayClick?: (e: React.SyntheticEvent<{}>, day: Date, modifiers: DayModifiers) => any;
         onDayTouchTap?: (e: React.SyntheticEvent<{}>, day: Date, modifiers: DayModifiers) => any;
         onDayMouseEnter?: (e: React.SyntheticEvent<{}>, day: Date, modifiers: DayModifiers) => any;
diff --git a/react-dom/index.d.ts b/react-dom/index.d.ts
index bf0a246211..00520fc6ed 100644
--- a/react-dom/index.d.ts
+++ b/react-dom/index.d.ts
@@ -28,7 +28,7 @@ declare namespace ReactDOM {
         container: Element | null,
         callback?: (component: T) => any): T;
     function render<P>(
-        element: ReactElement<P> | null,
+        element: ReactElement<P>,
         container: Element | null,
         callback?: (component?: Component<P, ComponentState> | Element) => any): Component<P, ComponentState> | Element | void;
 
@@ -57,7 +57,7 @@ declare namespace ReactDOM {
         callback?: () => any): void;
     function unstable_renderSubtreeIntoContainer<P>(
         parentComponent: Component<any, any>,
-        element: ReactElement<P> | null,
+        element: ReactElement<P>,
         container: Element,
         callback?: (component?: Component<P, ComponentState> | Element) => any): Component<P, ComponentState> | Element | void;
 }
diff --git a/react-native-swiper/react-native-swiper-tests.tsx b/react-native-swiper/react-native-swiper-tests.tsx
index c8dae8511e..93cdfcfd18 100644
--- a/react-native-swiper/react-native-swiper-tests.tsx
+++ b/react-native-swiper/react-native-swiper-tests.tsx
@@ -18,7 +18,7 @@ class SwiperTest extends React.Component<IProperties, IState> {
     super(props);
   }
 
-  public render(): React.ReactElement<any> | null {
+  public render(): React.ReactElement<any> {
     return (
       <Swiper
         style={styles.wrapper}>
diff --git a/react/index.d.ts b/react/index.d.ts
index f25e5c0afd..001484aa15 100644
--- a/react/index.d.ts
+++ b/react/index.d.ts
@@ -171,7 +171,7 @@ declare namespace React {
         setState<K extends keyof S>(f: (prevState: S, props: P) => Pick<S, K>, callback?: () => any): void;
         setState<K extends keyof S>(state: Pick<S, K>, callback?: () => any): void;
         forceUpdate(callBack?: () => any): void;
-        render(): JSX.Element;
+        render(): JSX.Element | null;
 
         // React.Props<T> is now deprecated, which means that the `children`
         // property is not available on `P` by default, even though you can
@@ -204,7 +204,7 @@ declare namespace React {
 
     type SFC<P> = StatelessComponent<P>;
     interface StatelessComponent<P> {
-        (props: P & { children?: ReactNode }, context?: any): ReactElement<any> | null;
+        (props: P & { children?: ReactNode }, context?: any): ReactElement<any>;
         propTypes?: ValidationMap<P>;
         contextTypes?: ValidationMap<any>;
         defaultProps?: P;
@@ -2628,11 +2628,9 @@ declare namespace React {
 
 declare global {
     namespace JSX {
-        interface JSXElement extends React.ReactElement<any> { }
-        type Element = JSXElement | null;
-
+        interface Element extends React.ReactElement<any> { }
         interface ElementClass extends React.Component<any, any> {
-            render(): JSX.Element;
+            render(): JSX.Element | null;
         }
         interface ElementAttributesProperty { props: {}; }
 
diff --git a/react/test/tsx.tsx b/react/test/tsx.tsx
index 0b0bc096ae..0531cb52c0 100644
--- a/react/test/tsx.tsx
+++ b/react/test/tsx.tsx
@@ -32,6 +32,3 @@ StatelessComponent2.defaultProps = {
         </text>
     </g>
 </svg>;
-
-const CustomComponent = (props: { flag: boolean }) => props.flag ? React.createElement('div') : null;
-const UseComponent2 = (f: boolean) => <CustomComponent flag={f} />;