A kinin-releasing enzyme was isolated from the venom of Agkistrodon halys ussuriensis using a very convenient two-step procedure consisting of HPLC anion-exchange chromatography. The relative molecular mass was estimated as 24,000 by SDS gel electrophoresis and an isoelectric point of pH 3.7 was established by gel isoelectric focusing. The kinin-releasing enzyme resembled a typical tissue kallikrein in the values of such physiochemical parameters, in its thermal stability, in its lack of activity towards fibrinogen and casein, and in its behaviour with potential inhibitors. Thus, the enzyme can be classified as a kallikrein-like enzyme.