Abstract: The aim of this experiment was to study the effects of LBP on the expression of Caspase3, Bcl2 and Bax proteins in spermatogenic cells of mice. Fifty adult male Kunming mice were randomly divided into five groups, which were A, B, C, D and E, with 10 mice in each group. Except the mice in group A which were injected with olive oil as control group, the mice in other four groups were intraperitonealy injected with 20 mg·kg-1 BPA for 7 days. Meanwhile, the mice in groups C, D, E were given different doses of LBP (50, 100 and 200 mg·kg-1) by intragastric administration consecutively for one week, the mice in control (A) group and model (B) group were treated with physiological saline. Histopathological changes of the testicular tissue were observed, immunohistochemical technique was applied to detect the expression of Caspase3, Bcl2 and Bax proteins. Results showed that BPA can enhance the expression of Caspase3 and Bax proteins (P<0.01), diminish the expression of Bcl2 (P<0.05). After supplement with different doses of LBP, the expression of Caspase3 were all significantly decreased in C, D and E groups than that in the model group (P<0.01). With the dose of LBP increasing, the expression of Bax was significantly decreased and the expression of Bcl2 gradually increased than that in the model group especially in the 200 mg·kg-1 LBP group (P<0.01). Compared with the model group, Bcl2/Bax ratio also increased obviously in groups B, C and D. Results suggest that LBP can restrain spermatogenic cell apoptosis through regulating the expression of apoptosisrelated genes, thus alleviate the reproductive damage induced by BPA on adult male mice.