This paper outlines the progress in recently reported trials of post-operative adjuvant chemotherapy for colorectal cancer. In American study, MeCCNU/VCR/5-FU therapy given following surgery has been reported to improve survival. More recently, regimens of 5-FU plus levamisole in Dukes C colon cancer can reduce mortality. But 5-FU/levamisole therapy did not have no effect on survival in Japanese trial. Recent two Japanese trials have demonstrated that regimens of mitomycin C plus 5-FU or regimens of mitomycin C puls UFT reduce pelvic recurrence rates and improve survival. Peri-operative portal vein infusion of 5-FU seems to demonstrate improved relapse-free and overall survival. Combined postoperative radiotherapy and chemotherapy for patients with rectal cancer seems to be effective. The most important problem is to establish an effective postopetative adjuvant chemotherapy for Japanese colorectal surgery.