PSK may refer to:
Businesses and organisations Österreichische Postsparkasse (PSK), a former postal savings bank in Austria Phi Sigma Kappa, a men's social and academic fraternity in North America Post Südstadt Karlsruhe, a German sports club Revolutionary Party of Kurdistan (Partiya Şoreşa Kurdistan, PŞK), an illegal political party active in Turkey
Science and technology Phase-shift keying, a digital modulation process Polysaccharide-K, a protein-bound polysaccharide Pre-shared key, a shared secret in cryptography
Other uses "P.S.K. What Does It Mean?", a 1985 song by Schoolly D P. S. K. Paha (fl. 1978), Ghanaian footballer and manager