Background: Polycystic ovarian syndrome (PCOS) is one of the mostcommon endocrine disorders affecting female fertility (Kousta et al., 1999).Objectives: This work aimed at evaluating the role of three dimensional powerDoppler ultrasonography as a method of diagnosis of polycystic ovary syndrome.Patients and Methods: A total of 40 women presented to the gynecologicalOutpatient Clinic at KEA, were chosen for this study. Group I: 20 womendiagnosed with polycystic ovarian syndrome, Group II: 20 women (the controlgroup). Results: This study revealed higher LH value, ovarian volume, vascularizationindex, flow index, vascularization flow index in the polycystic ovarian group comparedto the control group. Conclusions: This study shows that the new screeningtechnique of three-dimensional ultrasonography can complement twodimensionalultrasonography for the diagnosis of PCOS. It allows excellentspatial evaluation of PCOS with direct quantitative computations from the data.Evaluation of the ovarian stromal vascularity by 3 D power Doppler will furtherincrease our knowledge of this enigmatic syndrome. Recommendations: Werecommend the use of transvaginal ultrasound and Doppler assessment ofovarian vascularity in all cases of polycystic ovary disease and introduce the useof transvaginal ultrasound and Doppler as routine examination tools in all casesof polycystic ovary disease as they are found to be good diagnostic tools.