Getting Started on Windows#

The Qt library has to be built with the same version of MSVC as Python and PySide, this can be selected when using the online installer.


  • MSVC2022 or (MSVC2019) for Python 3 on Windows,

  • OpenSSL (optional for SSL support, Qt must have been configured using the same SSL library).

  • sphinx package for the documentation (optional).

  • Check the platform dependencies of Qt for Windows.


Python 3.8.0 was missing some API required for PySide/Shiboken so it’s not possible to use it for a Windows build.

Building from source on Windows 10#

Creating a virtual environment#

The venv module allows you to create a local, user-writeable copy of a python environment into which arbitrary modules can be installed and which can be removed after use:

python -m venv testenv
call testenv\Scripts\activate

will create and use a new virtual environment, which is indicated by the command prompt changing.

Setting up CLANG#

libclang can be downloaded from the Qt servers. for example, libclang-release_140-based-windows-vs2019_64.7z.

Note that from version 12 onwards, the prebuilt Windows binaries from LLVM no longer contain CMake configuration files; so they can no longer be used.

Extract the files, and leave it on any desired path, for example, c:, and set the environment variable required:

set LLVM_INSTALL_DIR=c:\libclang
set PATH=C:\libclang\bin;%PATH%

Getting PySide#

Cloning the official repository can be done by:

git clone

Checking out the version that we want to build, for example, 6.5:

cd pyside-setup && git checkout 6.5

Install the general dependencies:

pip install -r requirements.txt


Keep in mind you need to use the same version as your Qt installation

Building PySide#

Check your Qt installation path, to specifically use that version of qtpaths to build PySide. for example, C:\Qt\6.5.0\msvc2019_64\bin\qtpaths.exe.

Build can take a few minutes, so it is recommended to use more than one CPU core:

python build --qtpaths=c:\path\to\qtpaths.exe --openssl=c:\path\to\openssl\bin --build-tests --ignore-git --parallel=8

Creating Debug Builds#

  • Choose Custom Installation when installing Python and tick the options for debug binaries and libraries

  • Use venv to create a virtual environment and pass the debug binary:

    python_d.exe -m venv testenv_d
  • Use python_d.exe to invoke

Installing PySide#

To install on the current directory, just run:

python install --qtpaths=c:\path\to\qtpaths.exe  --openssl=c:\path\to\openssl\bin --build-tests --ignore-git --parallel=8

Test installation#

You can execute one of the examples to verify the process is properly working. Remember to properly set the environment variables for Qt and PySide:

python examples/widgets/widgets/