Tolerance to contact hypersensitivity was induced by feeding of different DNCB doses in mice. A total of 40 mice were divided into 4 groups(control group, 6 mg feeding group, 10 mg feeding group, 14 mg feeding group) in experiment I, Degree of tolerance to contact hypersensitivity was rneasured by incremert rate of ear swelling after challenge with DNFB. Experiment 2 was performed in the same method of cxperiment: I with addition of 3 mg DNCB feeding group. The increment ratee were significantly decreased in DNCB feeding groups in experirnent 1 and 2(p<0.0l). But there were no differences statisticalIy between increment rates of DNCB feeding groups.