Objective To explore the potential mechanism of Zhibai Dihuang Decoction（ 知柏地黄汤

ZDD） in treating male infertility caused by ureaplasma urealyticum infection. Methods Ureaplasma urealyticum standard strain liquid（ 2 ml per rat） was injected through bladder to establish rat model of ureaplasma urealyticum infection.The 64 successfully modelled rats were randomized into Chinese medicine group

western medicine group

the integrative medicine group and the model group

with 16 rats in each group

and another 15 rats were sat in the sham operation group. On the second day after model establishment

the sham operation group and the model group were orally administered 0. 9% sodium chloride injection（ 2 ml/d）

Chinese medicine group received crude drug of ZDD（ 1. 88 g/d）

Western medicine group received 4 mg/d of doxycycline

and the integrative medicine group was given equal amount of ZDD and doxycycline. Each group was treated for 21 days. The open degree of mitochondrial membrane pore（ m PTP） and the content of mitochondrial ATP

ATP and AMP in the sperm were measured and the energy charge（ EC） was calculated. Results Compared with those in the sham operation group

the open light absorbance of sperm m PTP in the model group decreased

ATP

ADP and EC decreased

while AMP increased（ P <0. 01）. Compared with the model group

the open light absorbance of sperm m PTP increased in all treatment groups

and ATP

ADP and EC in Western medicine group and the integrative medicine group increased while the AMP decreased（ P < 0. 05 or P < 0. 01）. Compared with Chinese medicine group

the open light absorbance of sperm m PTP in the integrative medicine group increased（ P < 0. 05）; ATP in the integrative medicine group was higher than that in Chinese medicine group and Western medicine group

and the ADP and EC in the integrative medicine group were higher than those in Chinese medicine group（ P < 0. 05 or P < 0. 01）. Conclusion ZDD could reduce the open degree of sperm m PTP in rats infected with ureaplasma urealyticum and maintain the energy metabolism of mitochondria

thereby improving the sperm quality

which may be one of the mechanisms for its treatment of infertility caused by ureaplasma urealyticum infection.