Aim of work: The aim of this study was to evaluate the value of laparoscopy in diagnosis of endometriosis in cases of unexplained infertility.

Objectives:To asses frequency cases of endometriosis in unexplained infertility cases.
To asses grades of endometriosis in unexplained infertility.

Methods: This cross sectional study "observational study". The study was carried at endoscopy unit at zagazig university hospital from July 2018 to January 2019.
Results: Sample size was calculated to be 24 case during 6 months assuming that rate of un explained infertility cases at Zagazig University Hospital is about 2-3 cases per month. Sample size was calculated using Epi info 6 by confidence interval 95% and power of true test 80%.
Conclusion: It is concluded that endometriosis is a common diagnosis in women with unexplained infertility and chronic pelvic pain. Laparoscopy should be indicated when diagnosis is suspected, together with tissue sampling and histopathologic examination. More research is required to find more accurate noninvasive tests and effective treatment to deal with this disease.

Key words; Unexplained Infertility, Laparoscopy hysterectomy, Single incision laparoscopic surgery, vascular endothelial growth factor