Objective To evaluate the safety and efficacy of combining radiofrequency ablation(RFA) with arsenious acid(AA) locally to treat liver VX2 tumor in rabbits,and to explore its mechanism.Methods Twenty-eight New Zealand White rabbits with implanted liver VX2 tumors were randomly divided into four groups: control group(n= 7),AA group(n=7),RFA group(n=7),and combination(RFA+AA) group(n=7).ALT was measured before treatment and on the day 0,day 3,day 7 and day 14 after treatment,meanwhile ultrasonic(US) examination was performed.All rabbits were killed 14 days after treatment.Vascular endothelial growth factor(VEGF) was examined by immunohistochemistry,and the relationship of VEGF and gross tumor volume was analyzed.Results Combination(RAF+AA) therapy caused little damage to hepatic function but had better inhibited tumor growth.The level of VEGF in AA,RFA and RAF+AA group was lower than that of the control group(P