For research the relationship between the expression of vascular endothelial growth factor (VEGF) and the cell proliferation. The expression of VEGF was evaluated while the cell cycle of hepatoma cell line Hep G2, which was synchronized at G0 phase with serum deprivation, and reinitiated with TPA and blocked with antisense oligonucleotides of c-jun. Results: Hep G2 cell did not express VEGF at G0 phase. TPA could induce the expression of VEGF as well as initiation of cell cycle. The antisense oligonucleotides of c-jun could prohibit the expression of VEGF and arrest the cell cycle at G0 phase. Conclusion: The fact that the expression of VEGF accompanies the initiation of cell cycle suggests that they be regulated by the same singnal pathway, the expression of VEGF may be a marker indicating the proliferation of hepatoma cells.