There are a lot of much more capable editors that support SCSS natively around, but if you really stuck using Notepad++, here's a custom syntax highlighting config XML file for you.
...my suggestion, anyway, is to check out SublimeText and Atom ;)
Please note that colors are based on the "Obsidian" theme bundled with Notepad++.
- In Notepad++, open the
Language
and menu and selectUser Defined Dialog...
- Click on the import button and select the XML file located in our ZIP file
- After restarting Notepad++ your files with the .scss extension should now be highlighted
- go to your Notepad++ folder then to
/plugins/APIs/
- duplicate the
css.xml
and rename this file toObsidian_SCSS.xml
Another similar project: http://www.marvinlabs.com/2012/08/03/scss-syntax-highlighting-for-notepad/