The arginine kinase was purified from muscle tissue of the shrimp, Littopenaeus vannamei. The crude extract was treated with CM-cellulose in a batch procedure. Fractionation of arginine kinase was performed by SephadexG-100 chromatography and followed by DEAE-cellulose 32 ion-exchange chromatography. The molecular weight of it was about 40 ku, as judged by SDS-polyacrylamide-gel electrophoresis. The enzyme remained stable at 25-55℃ within 60 min and inactivated at higher temperature (65℃). The activity of purified shrimp arginine kinase was remained stable in the range of pH 6.0-8.0. Treated with 10 mmol·L^-1 arginine, NaCl, KCl, MgCl₂, the enzyme activity significantly increased. However, the enzyme activity was obviously inhibited by its substrate analogs such as spermine, amino guanidine, CuCl₂, MnCl₂.