ABSTRACT: The aim of this study was to evaluate some hematological parameters in pediatric patients with chronic kidney disease (CKD) in children who are on hemodialysis (HD) and peritoneal dialysis (PD). It is characterized by its irreversibility. Deterioration of kidney function that gradually progresses to end-stage renal function illness. Over the past two decades, the incidence of CKD in children has increased Steady increase. The major health consequences of CKD include not only progression to kidney failure, but also increased risk of cardiovascular disease. The study was conducted in the dialysis unit of Al-Zahraa Teaching Hospital in Wasit governorate and the Child Protection Teaching Hospital -Medical City in Baghdad. During the period from November 2023 to April 2024. This study aimed to examination of risk factors (height, weight, age, sex, inheritance of the disease in the family, medical history, symptoms of the disease, other diseases, treatment methods) for CKD in general. The biochemical effect was also studied and blood indicators for patients on HD and PD purpose. For the purpose of studying the hematological of patients undergoing dialysis and comparing those results with their values in both HD and PD. This study was done on (80) Iraqi children (30) of them suffering from kidney failure and (50) of them was healthy with age range (1 day -17) years old. HD was performed for 22 children with CKD, and PD was performed for 8 patients with CKD. This study involved dividing patients into three Groups according to the age at which the disease begins, from (1 day-5 years), (6-11) years and (12-17) years, included 15 females and 15 males. Samples were collected based on the incidence of CKD and type of treatment, as well as the diagnosis of all patients according to international standard by the physician. The results of our study with regard to the hematological of patients undergoing PD showed a significant increase in the levels of (WBC) p ≤ 0.05 and also showed a significant decrease in the levels of (RBC, Hb, PCV, ESR) p ≤ 0.05. a non-significant increase in TSH levels p ≥ 0.05. The results of our study with regard to the hematological parameters of patients on HD showed a significant increase in the levels of (ESR) p ≤ 0.05 and a significant decrease in the levels of (WBC, RBC, PCV, Hb) p ≤ 0.05.