Abstract: Objective: To evaluate the effect of chemotherapy-induced amenorrhea (CIA) on the prognosis of breast cancer and to study the clinical significance of CIA. Methods:A total of 88premenopausal breast cancer patients were treat -ed with a combined therapy of paclitaxel and anthracyclines with4 cycles before and after surgery. The effect of neoadju-vant chemotherapy was evaluated according to the response evaluation criteria in solid tumors (RECIST). The pathologic complete response (pCR) rate was also calculated. All patients were followed up and their disease free survival (DFS) was summarized. The correlation among occurrence of CIA, neoadjuvant chemotherapy effect and DFS were analyzed using the statistical methods of chi-square test and Kaplan-Meier survival curve. Results: CIA occured in 64of the 88patients af -ter chemotherapy. Following the neoadjuvant chemotherapy, complete regression (CR) was seen in 22(25.0%) of the pa-tients, partial response (PR) was seen in 51(58.0%), stable disease (SD) was seen in12(13.6%), and progression of dis-ease (PD) was seen in 3 (3.4%). There is no correlation between the incidence of CIA and clinical effects of neoadjuvant therapy (P=0.104 ). pCR was found in 14patients after neoadjuvant therapy. The pCR rate was higher in the CIA group (21.9% ) than in the non-CIA group (0.0% ), and there were significant differences between the two ( P=0.009 ). After fol -low-up (median, 48months), local recurrence or distant metastasis occurred in4 patients from the CIA group and 10of the 24patients from the non-CIA group. There were significant differences in the DFS between the two groups ( P< 0.05). Conclusion: The occurrence of CIA seems to indicate a better prognosis for breast cancer patients treated with chemotherapy before and after surgery.