Abstract： Objective To investigate the impact of previous cystectomy for ovary benign cyst on ovarian reserve and pregnancy outcome in in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) cycles. Methods Totally 622 infertility patients were retrospectively investigated who underwent first IVF/ICSI-ET cycle in Reproductive Hospital Affiliated to Shandong University from January 2013 to June 2014. There were 153 cases who had been removed ovarian cyst by cystectomy surgeries recruited as study group, in which 44 cases of ovarian endometriosis cyst, 35 cases of benign ovarian teratomas, 67 cases of simple ovarian cyst and 7 cases of ovarian mucinous cystadenoma. In contrast, 469 infertility patients with tubal-factor infertility or male factor were included as control group. The age-matched women in the control group had no ovarian surgery previously. The indicators of ovarian reserve and pregnancy outcome were analyzed between two groups. The influence of different types of ovarian cysts on ovarian reserve and pregnancy outcome in IVF/ICSI-ET cycles were also studied, ovarian endometriosis cyst was studied as Group A, and Group B consisted of benign ovarian teratomas, simple ovarian cyst and&nbsp;mucinous cystadenoma. Results (1) The significantly lower serum antimullerian hormone (AMH) level (median: 1.92 versus 2.90 mg/L), antral follicle count (AFC; median: 12.0 versus 13.0), retrieved oocytes (12 ± 5 versus 13 ± 6) and the number of embryo cryopreserved (median:1.0 versus 3.0) were found in study group compared with control group (all P<0.05). There was no statistical difference between two group for the following parameters, such as basal FSH level, the total dosage of gonadotropin duration and the total dosage of gonadotropin (all P>0.05). A better clinical pregnancy rate was achieved in control group (61.6%, 241/391) than that in study group (61.4%, 81/132), but no significant difference was existed (P=0.96). (2) Compared to Group B, Group A had fewer AFC, lower serum AMH level, retrieved oocytes and the number of embryo cryopreserved (11±4 versus 13±5;1.65 versus 2.15 mg/L;9±4 versus 13±5;0 versus 2.0;all P<0.01). There was a lower clinical pregnancy rate in Group A than that in Group B [50.0% (19/38) versus 66.0%(62/94)], accompanying with higher abortion rate [3/19 versus 9.7%(6/62)], but no differences were observed (all P>0.05). Conclusions Ovarian reserve declines after the cystectomy for ovarian benign cysts and the cystectomy has a negative impact on IVF/ICSI-ET cycle, resulting in a decrease of the number of retrieved oocytes and the number of embryo cryopreserved, but do not influence clinical pregnancy outcome. Ovarian reserve is impaired more seriously by cystectomy for ovarian endometriosis cyst than other ovarian benign cyst.