Antimony potassium tartrate, also known as potassium antimonyl tartrate, potassium antimontarterate, or emetic tartar. It has the formula K2Sb2(C4H2O6)2, M.W. is 667.87 g/mol and CAS no: 28300-74-5. It is water soluble double salt of potassium and antimony of tartaric acid.

It is used as explosive cross-linker, also used in veterinary application and mordent in dyeing.