OBJECTIVE:To observe therapeutic efficacy and liver toxicity of chemotherapy combined with bevacizumab in the treatment of colorectal cancer liver metastases(CLMs). METHODS:126 CLMs patients were selected and randomly divided into chemotherapy group(54 cases)and combination group(72 cases). Chemotherapy group received FOLFOXIRI regimen:irinotecan 165 mg/m2+ oxaliplatin 85 mg/m2+ calcium folinate 200 mg/m2+ fluorouracil 2 g. Combination group was additionally given bevacizumab 5 mg/kg one day before chemotherapy on the basis of FOLFOXIRI regimen. A treatment course of 2 groups lasted for 2 weeks,and both received 12 courses of treatment. The pathological response,survival rate and toxic reactions caused by chemotherapy were compared between 2 groups. RESULTS:Pathological complete response proportion,tumor remission rating(TRG),the proportion of patients with tumor necrosis rate ≥50% in combination group were significantly higher than chemotherapy group, with statistical significance(P<0.01). The proportion of TRG4-5,TRG 1-3 progression-free survival in combination group were significantly higher than chemotherapy group,with statistical significance(P<0.05). The incidence of liver parenchymal necrosis in combination group was significantlg higher than chemotherapy group,there was statistical significance(P>0.05). CONCLUSIONS: Chemotherapy combined with bevacizumab can improve pathological response and the incidence of CLMs necrosis and doesn’t increase liver toxicity.