The unexplained infertility represents 10-15% of the reported infertility cases annually. More concern is recently directed towards unexplained infertility due to the enhancement of diagnostic tools & therapeutic modalities, which resulted into a better and larger treatment opportunity for infertility patients . In the diagnosis, efforts are directed towards finding an aetialogy either in the uterine tubes using varible endoscopic techiques or in the endomterial receptivity using ultrasonography & Doppler, or by finding causes related to the immune system or microbiology. In the treatment, better results are obtained due to the use of new medications for induction of ovulation or due to better use of variable methods of assissted reproductive technologies.