RSK may stand for:
- RSK Group, a UK consultancy group
- Republic of Serbian Krajina
- Robinson–Schensted–Knuth correspondence in mathematics
- Ribosomal s6 kinase, protein kinasesr
- RSK Sanyo Broadcasting, Japan
- Red Skin Kingz, Native American gang
- <syntaxhighlight lang="text" class="" style="" inline="1">rsk</syntaxhighlight>, the ISO language code for Pannonian Rusyn