Capecitabine(Xeloda®)has been a global standard drug for the treatment of colon cancer since large randomized controlled trials demonstrated its efficacy and safety in treating patients suffering from the disease. Few studies have been conducted to assess the effects of oral capecitabine treatment on Japanese patients. Therefore, we conducted this study to evaluate oral capecitabine as postoperative adjuvant chemotherapy in 50 patients who underwent surgery for stage III colon cancer at our department. Patients received an 8 courses treatment with capecitabine during the study, and the incidence of adverse events, treatment completion rate, and treatment compliance were assessed. Adverse events were reported in a total of 46 patients(92%). The most common adverse event was hand foot syndrome(HFS), reported in 39 patients(78%), whereas bone-marrow toxicity and diarrhea were reported in as few as 2(4%)and 3(6%)patients, respectively. Both these events were mild in severity, and no patients required hospitalization, nor were they associated with treatment-related deaths. The median treatment duration was 8 courses ranging from 3 to 8 courses, and the 8 courses treatment completion rate was 96%. The relative dose intensity, which was used as a treatment compliance index, is expressed as the actual dose taken by the patient divided by the dose planned at baseline. The median and mean of the relative dose intensity were 100%(ranging from 37% to 100%)and 93%, respectively. The results of this study showed that the safety profile of oral capecitabine therapy was generally favorable, with a lower incidence and lesser severity of life-threatening bone-marrow toxicity and diarrhea, although the treatment is still associated with frequent HFS. This is the great advantage of capecitabine when it is used as postoperative adjuvant chemotherapy for gastrointestinal cancer. Indeed, a satisfactory treatment completion rate was achieved in this study while maintaining a sufficient dose and treating HFS, by reducing the dose, interrupting treatment, or providing appropriate corrective measures.