The objective of investigating some biochemical parameters like urea, creatinine, Hb and other parameters as CRP and leptin in the serum of ESRD patients on hemodialysis pre-dialysis. Method: Sample of 250 cases which consists of the patient with ESRD, their mean ages were 52.66 ± 12.55 years with ranged from 18-83. Moreover, under hemodialysis treatment not less than three months. Apparently, 20 healthy subjects were selected as (control) for comparison. Results: The results showed that there was a significant increase (p<0.01) in the serum urea, creatinine, CRP, and leptin. While, revealed significant (p< 0.05) decrease in the levels of uric acid, serum glucose, albumin, inorganic phosphorus, potassium, Hb and platelet in patients before dialysis compared to the control group. Non-significant (p>0.05) is in total cholesterol, calcium and total protein in patients undergoing hemodialysis which was compared to the control group. It is concluded from the findings of the present study, it shows a highly significant increased serum concentration of leptin as well as, elevated serum values of CRP. Whereas a highly significant decrease in GFR and CrCl result from loss of the ability of the kidney to clearance. Also, abnormal mineral parameters and hematological parameters. According to the results of this study, serum total protein and cholesterol cannot be used, as a diagnostic marker of nutrition disorders in patients on regular hemodialysis requires further investigation and clarification.