Objective:To investigate the effects of low-dose of long-and short-acting gonadotrophin releasing hormone analogue(GnRH-a) agonist on patients with diminished ovarian reserve. Methods:Retrospective analysis was performed on 565 in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI)cycles,which are consistent with diminished ovarian reserve and using the low-dose long down-deregulation protocol. According to the type of GnRH agonist,they were divided into the long-acting group(group A)and the short-acting group (group B). Then,we compared basic situation,ovulation induction process and outcome of ET and FET cycle of the two groups. Results:There were no significant differences between groups A and B in the general situation and assisted reproductive method. Compared with group B,the egg number and the number of effective embryos of group A had no statistical difference. However,both gonadotripin(Gn)stimulation days and Gn doses were significantly higher in group A compared with group B. In the ET cycle,there was no significant difference in clinical pregnancy rate,abortion rate and delivery rate between group A and B. However,in the FET cycle,the clinical pregnancy rate,implantation rate and delivery rate of group B were significantly higher than those of group A. The cumulative clinical pregnancy rate and delivery rate of group B were also significantly higher than that of group A. Conclusion:Patient with diminished ovarian reserve can still use low-dose long down-deregulation protocol to obtain more effective embryos and fresh embryo transplant opportunity. The clinical pregnancy rates were also high. Long-acting GnRH-a increased the amount of Gn,and the clinical pregnancy rate of this group in FET cycle was lower. This study suggests that these patients use low-dose short-acting GnRH agonist protocol.