We report here on the multiple genital tract neoplasms in a 41-yr-old Korean woman with Peutz-Jeghers Syndrome (PJS). The patient presented with lower abdominal pain. Her previous medical history was PJS and breast cancer. Pelvic ultrasound showed a multilocular cyst at the right adnexal region, diagnosed as bilateral ovarian mucinous borderline tumors. An ovarian sex cord tumor with annular tubules was incidentally diagnosed together with a minimal deviation adenocarcinoma of the uterine cervix and mucinous metaplasia of both the Fallopian tubal mucosa and the endometrium. Although the cases of multiple genital tract tumors with PJS has rarely been reported, the present case appears to be the first in Korea in which the PJS syndrome was complicated by multiple genital tract tumors and infiltrating carcinoma of the breast. The clinical significance of the multiple genital tract tumors and breast cancer associated with PJS is reviewed.