Objective:To investigate the damage effect of bisphenol A (BPA)on the testis tissue of adult mice, and to reveal the reproductive toxicity of BPA in the body of animal and mechanism.Methods:40 KM mice aged 8 weeks were randomly divided into control group (according to the weight ratio of corn oil gavage), low dose of BPA group (100 mg·kg-1BPA),moderate dose of BPA group (200 mg·kg-1 BPA),and high dose of BPA group (400 mg·kg-1 BPA).4 weeks laster,the testis tissue was taken.The apoptotic rates in the testis tissue were detected by flow cytometry;the distribution and expression of Fas and FADD were measured by immunohistochemistry.Results:Compared with control group,the apoptotic rate,the expression rates of Fas and FADD in testis tissue of the mice in low dose of BAP group had no changes (P>0.05),while the apoptotic rates in the testis tissue and the positive expressions rates of Fas and FADD in moderate and high doses of BPA groups were increased (P<0.05).Compared with low dose of BPA group,the apoptotic rates and the positive expression rates of FAS and FADD in tests tissue of the mice in moderate and high doses of BPA groups were significantly increased (P<0.05).Compared with moderate dose of BPA group,the apoptotic rate and the positive expression rates of FAS and FADD in testis tissue of the mice in high dose of BPA group was significantly increased (P<0.05).The overexpression of Fas and FADD was positively correlated to the apoptotic rate in testis tissue in moderate dose of BPA group (r=0.430,P<0.05;r=0.238,P<0.01)and high dose of BPA group (r=0.637,P<0.01;r=0.359,P<0.01).Conclusion:BPA with content dose can increase the apoptotic rates of cells in testis tissue and the expressions of Fas and FADD.BPA’s reproductive toxicity may be closely associated with the activation of Fas signal pathway and resulting in massive apoptosis.