Abstract: Objective To investigate the effect of amtospheric traffic pollutantson male reproductive system in mice.Methods Fifteen Kunming male mice were randomly divided in to three groups(heavy pollution,moderate pollution group and non-pollution group).The mice in pollution groups were exposed to traffic pollution at field for 10 hours every day.Twenty-six days after the exposure,body and testis weight of the mice were weighted and the organ weight ratio was calculated.The testis and epididymis were collected and dyed with HE staining for observation of pathological changes under light micro scope.Results The average body weight,testicular weight of the mice in heavy pollution group were significantly lower than that of control group(25.60 vs 27.88 g,0.115 7 vs 0.140 2g;P<0.05).Compared to the control group,germ cell layers of the mice exposed to heavy pollution decreased from 5-7 layers to 1-2 layers,and that of the moderate pollution decreased from 5-7 to 3-4 layers with significant differences(P<0.01).Compared with the mice in control and moderate pollution groups,the number of spermin mice exposed to heavy pollution were significantly reduced with significant diffences(P<0.01).Conclusion The amtospheric transport pollutants have damage effects on male reproductive system in mice.