XPS (XML Paper Specification) viewer in Windows is used to open files of .xps format which are basically output of programs that can be directly printed into different formats.
However, to remove XPS viewer and XPS services which is available by default :
1. Open Control Panel > Programs and Features.
2. Select the link “Turn Windows features on or off” (admin rights needed for this).
3. Scroll down and uncheck the boxes next to XPS services and XPS viewer.
4. While doing this, a warning will pop up, hit Yes and continue.
By the way, this won’t uninstall the XPS viewer from Windows but will make it unavailable, to enable it, check the boxes again if needed.