Abstract: Objective：To study the value of preoperative treatment of gonadotrophin releasing hormone agonist （GnRHa） in laparoscopic excision of ovarian endometriotic cysts（LEOEC）. Methods：64 cases of LEOEC were analyzed retrospectively，of which 35 cases（study group） accepted the preoperative treatment of GnRHa for 3 months，and the other 29 cases （control group） accepted no preoperative treatment. Results：The operating time，blood loss，the cases whose ovary were coagulated and whose ovarian endometriotic cyst could be almost entirely separated in the study group and control group were （53.0±17.6） min versus （74.0±27.9） min，（29.0±13.7） mL versus （43.0±27.2） mL，6 cases（17.1%） versus 18 cases（62.1%），23 cases（65.7%） versus 1 cases（3.45%），respectively. Conclusion：Preoperative treatment of GnRHa is helpful for LEOEC，which includes minimizing the operating time and the blood loss，making the procedure more easier.

Key words: Endometriosis, Gonadotrophin-releasing hormone, Laparoscopes, Ovary