OBJECTIVE： To observe therapentic efficacy of bevacizumab combined with irinotecan+leucovorin+fluorouracil （FOLFIRI） plan in the treatment of advanced colon cancer， toxic reaction and patients’survival rate. METHODS： A total of 113 patients with advanced colon cancer admitted to the oncology department in our hospital from Jan. 2010 to Aug. 2014 were randomized into observation group 1 （40 cases）， observation group 2 （39 cases） and control group （34 cases）. Three groups received FOLFIRI； observation group 1 and 2 were additionally given Bevacizumab injection 5 and 7.5 mg/kg 14 d as a treatment course， for 8 cycles. Clinical efficaices as well as the positive rate of VEGF-A， immune indexes （the proportion of CD3+， CD3+CD4+， CD3+CD8+ in T cell subset） before and after treatment， the incidence of toxic reaction， 1-year and 2-year survival rates were compared among 3 groups. RESULTS： The total response rate of observation group 1 and 2 were significantly higher than control group， and the positive rate of VEGF-A in observation group 1 and 2 were significantly lower than control group， with statistical significance （P＜0.05）. The proportion of CD3+， CD3+CD4+ and CD3+CD8+ in 3 groups were significantly lower than before treatment， but observation group 1 and 2 were significantly higher than control group， with statistical significance （P＜0.05）. The incidence of grade hypertension （grade 3-4） in observation group 1 and control group were lower than observation group 2； the incidence of leucopenia （grade 3-4） in observation group 1 and 2 were significantly lower than control group， with statistical significance （P＜0.05）. There was no statistical significance in 1-year survival rate among 3 groups （P＞0.05）. 2-year survival rate of observation group 1 and 2 were significantly higher than control group， with statistical significance （P＜0.05）. CONCLUSIONS： For advanced colon cancer， different doses of bevacizumab combined with FOLFIRI have significant synergistic effect， can effectively inhibit VEFG-A， play a role of immune protection and anti-toxic side effects， and prolong the survival time. The incidence of hypertension in patients treated with low-dose bevacizumab is relatively lower and the safety is better.