One alkaline protease from Actinomucor elegans AS3.2778 was purified 22.7 fold with a total yield of 16.1% and a final specific activity of 6094 u/mg protein. The enzyme was purified using ammonium sulfate precipitation, ion exchange chromatography, hydrophobic chromatography and size exclusion chromatography method, and its properties were also investigated. The molecular weight of this enzyme is 32 kDa with SDS-PAGE method, optimum temperature is 60℃, optimum pH is pH 8.5 to 10.5, it is stable in the pH range of 6.0 to 9.0 at < 40℃ temperature, and being completely inhibited by the serine protease inhibitor, PMSF, indicated that it belongs to the serine protease family. Specificity test indicated this protease has extensive selectivity to peptide bones, especially to peptide bones composed of Leucine residue.