The relative risk of cancer recurrence with postoperative adjuvant FOLFOX/CapeOX therapy(Ox)for stage III colorectal cancer is reduced by approximately 20%when compared to that with fluorouracil plus Leucovorin. We performed a questionnaire survey to evaluate the quality of life(QOL)and extent of side effects in patients who received adjuvant chemotherapy. In order to evaluate the risks and benefits of oxaliplatin administration, we also examined the differences in awareness of oxaliplatin side effects between patients and medical staff. Responses were obtained from 147 patients, 54 doctors, and 84 nurses. Analysis of the patient responses showed higher current QOL scores regardless of the chemotherapy regimen, although patients in the Ox group had a high rate of residual sensory peripheral neuropathy. In the Ox group, 81% of patients responded that the side effects were moderate. In contrast, 40% of medical staff identified the side effects of oxaliplatin as severe, which differed from that reported by the patients. Considering that Ox adjuvant chemotherapy may reduce the risk of recurrence by approximately 20%, the risk/benefit balance is acceptable.