A proteinase, which has important work on turbot digestive, was purified from turbot （ Scophthalmus maximus L. ） and its major physical and chemical characteristics were studied and reported in this article. The intestine proteinase extraction was prepared through homogenate and centrifugation by Tris-HCl buffer at low temperature. The supematant was purified through ammonium sulfate grading precipitation further and the active component was dialyzed and concentrated. Then the condensed proteinase was purified by means of DEAE-Sepharose Fast Flow anion-exchange chromatography with an elution of a linear gradient of 5 mmol?L^-1 Tris-HCl buffer （pH 8.5） containing 1.0 mol?L^-1 NaCl. At last, the. pure enzyme was obtained through Sephadex G-100 chromatography with an elution of 5mmol?L^-1 Tris-HCl buffer （pH 8.5）. The purity of the purified intestine proteinase was confirmed by the presence of a single band on SDS-PAGE. The relative molecular mass of this enzyme was determined to be about 58 kD. By using casein as substrate to measure proteinase activity, the characterization of turbot intestine proteinase was made. The enzyme is stable at pH 6.0 - 11.0 and temperature below 30℃. When the temperature rose, there was a rapid decline of its stability. The enzyme showed maximum activity at pH 9.0 and 50℃. When the temperature declined, the optimum pH of enzyme showed a trend of moving to alkaline. And when the action time prolonged, the optimum temperature of enzyme showed a fiend to decline. Furthermore, the enzyme is activated by Mn^2＋ and inactivated by Cu^2＋ ,Zn^2＋,Ag^＋,Fe^3＋ . In further studies, it was inhibited by SH-enzyme inhibitors such as p-Hydroxymercuribenzoate （ PCMB ） and N-bromosuccinimide （ NBS ） remarkably, and partially inhibited by tosyl-lysine chloromethyl ketone （TLCK）. Using casein as the substlate, the Km value of enzyme is 2.92g?L^-1 at pH 9.0,50℃. The result showed the enzyme seemed to be a SH-enzyme.