Objective To assess the value of arsenious acid in treatment for metastatic liver cancer and inspect its adverse reaction through comparison between the therapeutic effect of arsenious acid-FOLFOX4 combined chemotherapy and that of single FOLFOX4 chemotherapy. Methods Twenty-six patients with metastatic liver cancer were selected from July 2006 to December 2007 in Huadong Hospital. All the cases were averagely divided into therapy group and control group randomly, arsenious acid combined FOLFOX4 chemotherapy was performed in therapy group and single FOLFOX4 chemotherapy in control group. Results The total of 26 cases completed at least 2 cycles of arsenious acid-FOLFOX4 combined chemotherapy or single FOLFOX4 chemotherapy. During 6-24 months follow-up (median 12.5 months), the average survival time of the therapy group was 242 d, the median survival time was 281 d, and the average survival time of the control group was 227 d, the median survival time was 246 d, there was no statistical difference between two groups (Pgt;0.05). Pain: There were 2 cases of complete remission (CR), 5 cases of partial remission (PR), 2 cases of stable disease (SD) in therapy group, the objective effect (CR+PR+SD) was 9 cases. There were 1 case of CR, 3 cases of PR, 2 cases of SD in control group, the objective effect (CR+PR+SD) was 6 cases. Objective efficacy: There were no CR cases in two groups. In therapy group, there were 5 cases of PR, 6 cases of NC, 2 cases of PD, the objective effect (CR+PR) was 5 cases, the benefit (CR+PR+NC) was 11 cases. In control group, there were 2 cases of PR, 4 cases of NC, 7 cases of PD, the objective effect (CR+PR) was 2 cases, the benefit (CR+PR+NC) was 6 cases. There was no significant difference of the objective effect between two groups (Pgt;0.05), but the benefit was significantly different (Plt;0.05). The major toxic reactions were digestive tract side effect, hepatic and hematological toxicity in two groups. Conclusions Arsenious acid-FOLFOX4 combined chemotherapy can lead to good therapeutic effect. Arsenious acid will not increase the adverse reaction of normal chemotherapy.