ImportError: No module named flask

  1. Open a terminal window.

  2. Check if Python is installed by running the following command:

python --version

  1. If Python is not installed, install it by downloading and running the installer from the official Python website (

  2. After installing Python, check if the pip package manager is installed by running:

pip --version

  1. If pip is not installed, install it by following the instructions on the official pip website (

  2. Once pip is installed, install Flask using the following command:

pip install flask

  1. After the installation is complete, create a new Python file (e.g., and import the Flask module:

python from flask import Flask

  1. Save the file and run it using the following command:


This step assumes that you have created a simple Flask application in the file.

  1. If you encounter the error "ImportError: No module named flask," it indicates that Flask is not installed correctly. Revisit steps 6 and 7 to ensure that Flask is installed using the correct pip command and that the import statement in your Python file is accurate.

  2. If the issue persists, consider checking your Python environment, ensuring that you are using the correct Python version and that the pip executable corresponds to the Python interpreter you are using.

  3. Additionally, confirm that there are no typos or syntax errors in your file and that it is located in the correct directory.

  4. If the problem still exists, try creating a virtual environment to isolate your project dependencies and repeat the installation steps within that virtual environment.

  5. If none of the above steps resolve the issue, seek assistance from relevant forums or communities for further troubleshooting.

Note: Steps may vary slightly based on the operating system and specific development environment you are using.