【Abstract】Objective To investigate the change of vascular endothelial growth factor (VEGF) expression in HepG2 cells under hypoxia. Methods HepG2 cells were cultured under hypoxia（hypoxia group） and normal condition (control group). VEGF expression of HepG2 cells was examined by immunohistochemical staining. The growth of HepG2 cells was examined by MTT colorimetry and cell count. VEGF level in the culture medium was measured by ELISA.Results After 48 h and 72 h of culture, the growth rate of HepG2 cells in hypoxia group was lower than that in control group (P＜0.05). The cell count in hypoxia group (2.51×104/μl and 2.69×104/μl, respectively) was much lower than that in control group(3.01×104/μl and 3.52×104/μl) after 48h and 72h of culture (P＜0.05). In hypoxia group, VEGF level in the culture medium after 24 h and 48 h was higher than that in control group (P＜0.05, P＜0.01). Conclusion Hypoxia may enhance the VEGF expression in HepG2 cells and this could be the reason of high expression of VEGF after transcatheterized hepatic arterial chemoembolization.