A thrombin-like enzyme was purified from the venom of the snake Agkistrodon acutus. It was shown to be a single band both in SDS-PAGE and IEF. Its molecular weight is about 38 ku and isoelectric point is near 4.0. Also, its 15 amino acid sequence of N-terminal was obtained. It is VIGGVECDINEHRFL. It has high homology with thrombin-like enzymes from other snake venoms.