Abstract: Objective : Conventional chemotherapy for patients with breast cancer may lead to permanent amenorrhea in advance. In this trial, Zoladex was used to protect the ovarian function of the patients with breast cancer requiring for fertility or/and maintenance of the normal hormone level before chemotherapy. Methods : From December 2004 to December 2006, 63 patients with breast cancer requiring for fertility or/and maintenance of the normal hormone level were randomly divided into the test group (31 cases) and the control group (32 cases). The patients in the test group were treated with Zoladex 3.6 mg iH qd and then with chemotherapy after one menstrual cycle. Zoladex was used at 3.6 mg iH qd every month subsequently. The chemotherapy regimen was AC (cyclophosphamide 50mg/m² d₁ + adriamycin 50 mg/m² d₁ once a week, x4) or AC-T (cyclophosphamide 50mg/m² d₁ + adriamycin 50 mg/m 2 d1 once a week, x4; follow paclitaxel 135 mg/m 2 d1 once a week, x4). The patients in the control group were treated with conventional chemotherapy regimen of AC or AC-T. We compared the menstruation status after the chemotherapy between the two groups. Results : All of these 63 patients completed the treatment. The rates of the return of menstruation in the test group and the control group were 67.9% and 46.9%, respectively (P =0.027). Conclusion : Conventional chemotherapy may lead to permanent amenorrhea in advance and the recovery of menstruation is age-re-lated. Zoladex administered before chemotherapy can effectively protect the ovarian function and can satisfy the patients with breast cancer requiring for fertility or/and maintenance of the normal hormone level.