A study was to evaluate the efficacy and clinical utility of second look operation in the managements of malignant ovarian tumor at the Department of Obstetrics and Gynecology, Kosin medical colleage from January 1986 to September 1993. Of 220 patients diagnosed as ovarian cancer, 48 patients who had underwent primariy laparotomy were performed second look operation. Thirty-seven patients were found to have no evidence of disease. The result revealed that negative second look operation rate was noted 96.3% at stage I, 66.6% at stage II, 50.0% at stage III, and 42.9% at stage IV and total negative second look operation rate was 77.1%. The 2 year survival rate for stage I, II, III, IV were 85.2%, 66.6%, 50.0% and 42.9% respectively. The survival rate of negative second look operation was 86.5%, that of positive second look operation was 18.1%. In conclusion, second look operation in early stage ovarian cancer need to be justified.