ObjectiveTo establish the in vitro culture model of hepatitis B virusinfected human choriocarcinoma BeWo cells, and evaluate the mechanism of HBV intrauterine infection.MethodsBeWo cells were infected with the serum containing high level of HBV, HBV DNA load in the intracellular and supernatant were detected by realtime PCR; supernatant HBsAg and HBeAg quantitative assay was performed by chemiluminescent microparticle immunoassay; expression of HBsAg and HBcAg in the infected cells was detected with SABC immunohistochemistry.ResultsIn the first passage of infected BeWo cells, the intracellular and supernatant HBV DNA load increased with time, and reached peak 120 hours after infection; In the subsequent passages, the intracellular and supernatant HBV DNA load decreased gradually and became negative after the fifth passage. The supernatant HBsAg quantity in the first passage increased with time, in the firstthird passages were all tested as positive, but decreased gradually, all were negative after the fourth passage. The supernatant HBeAg quantity was negative in primary and subsequent passages ; The dyed HBsAg and HBcAg in the firstthird passage cells showed positive.ConclusionHBV can infect BeWo cells and express in subsequent passages, BeWo cells can be used to study the mechanism of HBV intrauterine infection.