This study was performed on 80 Subjects from Kasr El Aini hospital-Cairo university, Internal Medicine and Nephrology Department and Kasr ElAini Nephrology and dialysis center. The subjects were divided into 2groups:-Group 1:-60 patients CRF on regular hemodialysis more than 3months with follow up for 2 years. Group 2:- 20 controls with Age, sex andBMI matched. Each Subject was subjected to full history taking, full clinicalexamination and laboratory investigations including:-(S.creatinine, Bl.urea, S.calcium, S.phosphorus, P.T.H, S.cholesterol,S.triglyceride, S.albumin , and OPG{Osteoprotogerin}) and plain x-ray onboth hands, pelvis and lateral abdominal X-ray to detect vascularcalcification as a simple and noninvasive method and two dimensionalEchoheart to detect Valvular calcification.OPG level showed significant difference between the studied groups asin CRF=5.4±2.8 and controls=0.96±0.41 with significant P-value <0.001.In multiple regression analysis showed that vascular calcification detectedby X-Ray and valvular calcification by Echoheart was statisticallysignificant correlated with serum OPG level in hemodialysis patients withsignificant X-ray calcification score p value <0.05 and over all valvularcalcification with p value < 0.001.We concluded that there is strong positive relationship between OPGand both vascular and valvular calcification in hemodialysis patients. Thispositive correlation may open the gate for routine estimation of this agent asa surrogate marker of cardiovascular calcification in hemodialysis patients.