In order to evaluate the results on successful adjuvant chemotherapy in resected gastric cancer we performed a randomised trial on 134 patients in two arms: a control one with no further treatment after surgery versus a treatment arm given mitomycin-C (MMC), 20 mg/m2 intravenously one day every 6 weeks for four courses, starting before the sixth week after surgery. The median follow-up was 105 months. In the control arm, 49 out of 66 patients died due to recurrence, versus 40 out of 68 patients in treatment arm. Actuarial survival curve was statistically significant (P < 0.025) in favour of the treatment group. Liver metastases were lower in adjuvant group than in the control group (8/68 versus 19/66). Toxicity was mild. Main toxic effects were thrombocytopenia, leukopenia, nausea and vomiting. A pelvis renal cancer as a second malignancy 8 years after gastric cancer was observed. In that particular case MMC was given after surgery. We conclude that adjuvant chemotherapy based on MMC given in the early period after surgery, improves survival rate in gastric cancer resected patients.