Objective The mutant gene of BALB/c hairless mice affects skin and coat structure, but whether can it affect the immune function. Methods the parameters of CD4 +,CD3 +,CD8 +,CD19 +,IgG were tested by FCM and ELISA.Results 1.There were no significant differences in mice between sexes. 2. The parameters of the hairless mice were lower than those of other phenotypes. The parameter of CD8 + was significantly different by statistics. There were no significant differences among IgG of three phenotypes.Conclusion The mutant gene of BALB/c hairless mice affected the immune function.