The results of surgery: mean duration of surgery: 62.0 ± 21.8 minutes; got the tumor totally: 96.88%; mean of blood loss in surgery: 48.5 ± 16.2 ml; mean time in hospital after surgery: 5.2 ± 1.4 days. Conclusions: The ASRM score has improvement after using the GnRHa therapy for pre-operative severe endometriosis and ease of surgery.