Background:although the majority of infertile couples was found to have an identifiable male or female factor, 15–30% was categorized as having ‘‘unexplained infertility''. The endometrium is considered to be a key determinant in successful implantation. Endometrial receptivity is regulated by many factors including endometrial perfusion. Aim of the Work: this study aimedto detect the role of the two dimensional ultrasound and Doppler ultrasonographic uterine markers of implantation in patients of unexplained infertility compared to fertile participants. Patients and Methods: the study was performed on 50 patients presented to the outpatient clinic in Al-Hussein, Bab El-Shearia (Sayed Galal) Hospitals, Al-Azhar University from October 2017 to August 2018 and they were categorized into two groups: Group A (Patients group): it was included 30 participants presented with unexplained infertility. Group B) (Control group) who included 20 fertile women coming for contraception. Results: there was a significant statistical difference as regard the endometrial thickness between cases and controls, and the controls had a thicker endometrium. Lower pulsatility index (PI) in uterine artery in the controls compared to the infertile group. Increased sub endometrial vascularization in the controls compared to the infertile group. Conclusion:ultrasound as well as Doppler studies of the endometrial and subendometrial vascularization had a role in predicting endometrial receptivity. Uterine artery Doppler study and the endometrial thickness measurement had a role in detection of uterine receptivity.