Peroxidase is a good symbol of genetic message expression.The analysis of isozyme Peroxidase of leafbud and stem find that the isozymograms of peroxidase have apparent difference between the male plant and female plant of S.sphenanthera Rehd.& Wils.The isozymograms of female plant leaf is three enzyme zong more than male plant's,and can identify male plant and female plant of S.sphenanthera Rehd.& Wils.