Abstract: Objective：To study the effect of kaempferol on the BaP induced apoptosis in human chorionic trophoblast cells HTR8/SV neo. Methods：10 μmol/L BaP were added 0.01，0.1，1 μmol/L kaempferol jointly deal with human HTR8/SV neo cells 48 h，observed cells growth under the inverted microscope，Gimesa staining and Hochest33342 fluorescent staining observed morphologic changes，determination of apoptosis rate changes by flow cytometry. Results：① Flow cytometry results showed that BaP alone cell viability was （72.58±0.29）%, with 0.01,0.1,1 μmol/L kaempferol the role of cell viability was （84.96±1.34）%,（89.54±1.64）% and （91.01±1.26）%, respectively, compared with BaP alone group, the differences were statistically significant（P＜0.01）. ②BaP alone can cause cell chromatin condensation，apoptotic bodies and other typical apoptotic morphology，dense hyperchromatic nuclei，fragmentation shape. Conclusions：Kaempferol showed a protective effect on BaP induced apoptosis in HTR8/SV neo cells.

Key words: Air pollution, Trophoblasts, Placenta, Apoptosis, DNA damage