Background:End-stage renal disease has become a public health concern worldwide. Type 2 diabetes is associated with significantly accelerated rates of diabetic nephropathy. There are controversies about the role of intact parathyroid hormone (iPTH) in the pathogenesis of osteodystrophy among diabetic patients on regular hemodialysis. We aimed to estimate serum levels of iPTH, 25-hydroxyvitamin D and to clarify the possible relationships between iPTH and HbA1c ;which reflect the glycemic control as well as other clinical and biochemical parameters in end-stage renal disease patients on regular hemodialysis. Subjects and methods: A case-control study of 84end-stage renal disease patients on maintenance hemodialysis thrice weekly.Patients were stratified into three groups;group1:28 diabetic patients with good glycemic control(HbA1c < 7), group 2:28 diabetic patients with poor glycemic control(HbA1c >7), and group3:28non diabetic patients, In all studied participants,blood urea, serum creatinine , calcium, phosphorus, albumin, alkaline phosphatase, lipid profile, HbA1c, fasting blood glucose (FBG),post prandial blood glucose (PPBG) and25-hydroxyvitamin Dwere measured.Also, we estimate serum iPTHlevels by ADVIA CENTAUR instrument using Chemiluminescence principle. Results:Non diabetic patienton chronic hemodialysis had significantly higher values of serum 25-hydroxyvitamin D,serum iPTHmore than diabetic group, moreover diabetic patients with poor glycemic control had significantly lower values of serum 25-hydroxyvitamin D and serum iPTH, compared to good glycemic control.In diabetic patients with poor glycemic control,iPTHlevel was negatively correlated with Alkaline phosphatase,post prandial blood glucose, fasting blood glucose, as well as HbA1c. In patients with good glycemic control serum iPTHlevel was positively correlated with25-hydroxyvitamin D., there were significant negative correlations betweeniPTH level and creatinine, alkaline phosphatase, phosphorous, albumin, post prandial blood glucose, fasting blood glucose, as well as HbA1c.Stepwise linear regression analysis showed that, serum iPTH levels were independently correlated with 25-hydroxyvitamin D with diastolic blood pressure,