OBJECTIVE,This study aims to compare the female sexual function in breast cancer patients, who have been administered breast-conserving surgery to the patients having undergone modified radical mastectomy.,METHODS,Forty-four breast-conserving surgery and 27 modified radical mastectomy patients were included in this study. All patients completed chemotherapy and radiation therapy after surgery. Modified radical mastectomy patients, who received breast reconstruction surgery afterwards, patients whom experienced local recurrence or distant organ metastases or patients over 50 years of age were excluded from this study. Each patient's sexual function was evaluated using the Female Sexual Function Index, six months after the completion of their treatment.,RESULTS,Between breast-conserving surgery and modified radical mastectomy groups, no significant difference of age, height, weight, and body mass index was observed. Although mean sexual desire (4,13 vs 3,97), arousal (3,72 vs 3,16), lubrication (3,76 vs 3,44), orgasm (3,90 vs 3,38), satisfaction (3,07 vs 2,50), pain (4,07 vs 3,82) and total scores (22,65 vs 20,27) were all higher in patients with breast-conserving surgery, only arousal, orgasm and total scores were significantly higher (p: 0,025, p:0,017 and p: 0,017, respectively).,CONCLUSION,In the treatment of breast cancer, the conservation of patients' sexual function is an important issue. Our study demonstrates higher female sexual function in breast-conserving surgery patients, highlighting the statistical difference of the arousal, orgasm and total scores of the Female Sexual Function Index, comparing with modified radical mastectomy patients.