Abstract: In the present paper ,11 variables of mandibles of adult male mice from three strains were measured. The mice involved were 16 KM，10 BALB/c, 10 ICR respectively.The variables of mandibles were analyzed by Enter Independents Together and Use Stepwise Method of SPSS for Windows 10.0. These variables were used to establish discriminant functions for distinguishing among the three differ-ent strains. The correct discriminant rates both reach 100% by original grouped cases；the correct discriminant rates both reach 97.2% by cross-validated grouped cases.