The feasibility of treatment containing bevacizumab (BV) for elderly patients is not well established. We investigated the safety of treatment containing BV for advanced or metastatic colorectal cancer in elderly patients. From June 2008 to December 2010, 22 patients were treated with BV in our hospital. We classified them into three groups: less than 65 years (group A: 8 patients), 66-75 years (group B: 9 patients), and more than 76 years (group C: 5 patients). Then, we compared the adverse events involving BV. The patient median age was 71. 5 (range 45-84)years old; 10 patients were treated in first-line therapy and 12 patients in second-line therapy or beyond. The number of patients with hypertension was one (12. 5%) in group A, 3 (33. 3%)in group B, and 3 (60%) in group C. Treatment was continued in 4 patients, and discontinued in 18. The reasons for discontinuing BV treatment were tumor progression in 14 patients, toxicities in 3 patients, and degradation of performance state in one patient. BV-associated adverse events had a tendency to become severe with aging, and patients for whom BV treatment was discontinued because of toxicities were all in group C. Severe adverse events of rectal bleeding, cerebral hemorrhage and cerebral infarction were observed in three patients. These patients had risk factors for BV-associated adverse events such as hypertension or a history of radiation therapy, besides the risk factor of age. It is suggested that BV-associated adverse events are highly frequent and severe in elderly patients. Especially in patients over 76 years old, risk factors such as hypertension and severe adverse events were observed. The administration of BV for elderly patients should be considered very carefully.