Aspergillus terrus has been used in this study for the production of proteases. The optimum conditions for proteases production have been achieved by growth on mineral salts medium supplemented with 4%wheat bran, 4% starch and without additional nitrogen source, using submerged fermentation. Purification of Aspergillus terrus proteases was performed using ammonium sulphate precipitation at 80%, chromatography on Sephadex G-100 and on DEAE-cellulose columns. The purified enzyme was active at 55°C, pH 7, stable till 45°C and at pH range 6-11 and inhibited with PMSF indicating that it is a serine protease. The purified enzyme had a Vmax value of 588.2 U/ml and Km value of 1.64 mg/ml. Studying the anticoagulant potency of the purified serine protease show its prolonging action on the extrinsic coagulation pathways using prothrombin time (PT) bio-assay.