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There are several reasons why the error “Component cannot be used as a JSX component” appears:

1. Returns an array of JSX elements instead of a single element.
2. Return any value other than a JSX element or null from a component.
3. React typings with outdated versions.

Here is an example that produces the above error

// ⛔️ 'App' cannot be used as a JSX component.
// Its return type 'Element[]' is not a valid JSX element.
// Type 'Element[]' is missing the following properties from type 'ReactElement<any, any>': type, props, key
const App = () => {
  return ['a', 'b', 'c'].map(element => {
    return <h2 key={element}>{element}</h2>;
  });
};

export default App;

The problem is that we're returning an array of JSX elements, not a single JSX element.

To fix this error, we have to divwrap the array using a React fragment or a <div> element.

const App = () => {
  return (
    <>
      {['a', 'b', 'c'].map(element => {
        return <h2 key={element}>{element}</h2>;
      })}
    </>
  );
};

export default App;

Now our component returns a single JSX element, so the error is resolved.

Fragments are used when we need to group sublists without adding extra nodes to the DOM.

We may also see a more verbose snippet syntax used.

import React from 'react';

const App = () => {
  return (
    <React.Fragment>
      {['a', 'b', 'c'].map(element => {
        return <h2 key={element}>{element}</h2>;
      })}
    </React.Fragment>
  );
};

export default App;

We can also use a wrapper div element to return a single JSX element from your component.

Another common cause of the “Component cannot be used as a JSX component” error is when we return anything other than a JSX element or null from a component, or forget to return a value.

// ⛔️ 'App' cannot be used as a JSX component.
// Its return type 'undefined' is not a valid JSX element.
const App = () => {
  // 👇️ this returns undefined
  return
  <h2>hello world</h2>
};

export default App;

The App component returns undefinedbecause we put the return statement on one line and the JSX code on the next line without using brackets.

We are not allowed to return from a component undefined, so the error occurs.

To resolve this error, make sure the code we return is accessible.

const App = () => {
  return (
    <div>
      <h2>hello world</h2>
    </div>
  );
};

export default App;

If we are sure to return a single JSX element or null from our React component but the error persists, try updating our React types.

Open a terminal in the root directory of your project (where your package.json file is located) and run the following command:

# 👇️ 使用 NPM
$ npm install --save-dev @types/react@latest @types/react-dom@latest

# 👇️ 如果你还想更新 react 和 react-dom
$ npm install react@latest react-dom@latest

# ------------------------------

# 👇️ 使用 YARN
$ yarn add @types/react@latest @types/react-dom@latest --dev

# 👇️ 如果你还想更新 react 和 react-dom
$ yarn add react@latest react-dom@latest

This command will update our version of React typings.

Make sure to restart the development server and IDE if necessary. The development server will not pick up changes until we stop and rerun npm startthe command.

If the error is not resolved, try deleting the node_modules and package-lock.json (not package.json) files, re-running npm installand restarting the IDE.

# 👇️ delete node_modules and package-lock.json
$ rm -rf node_modules
$ rm -f package-lock.json
$ rm -f yarn.lock

# 👇️ clean npm cache
$ npm cache clean --force

$ npm install

If the error persists, make sure to restart the IDE and the development server. VSCode often crashes and sometimes restarting can fix the problem.