Background: We aimed to study Interleukin 10 gene polymorphism and evaluate its prognostic significance in children with primary immune thrombocytopenia. Methods: The study was conducted at Pediatric Hematology Outpatient Clinic on 63 ITP patients who were divided into: 21 patients with recently diagnosed ITP, 21 patients with persistent ITP, and 21 patients with chronic ITP. As a control group, 21 children of the same age and gender who appeared to be in good health were included. The polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP) was used to examine IL10 (-627) gene variants in both patients and controls. Results: There was highly significant difference between patients and controls as regards frequency of A and C alleles of IL10 (627) where A allele was more prevalent in patients than controls. Among patients, A allele was more prevalent in chronic ITP patients compared to newly diagnosed patients or those with persistent ITP. The AA genotype was more prevalent in patients than controls. Among patients, the AA genotype was more prevalent in those with chronic ITP than newly diagnosed patients or those with persistent ITP. Conclusion: We concluded that IL-10 gene polymorphism may contribute to susceptibility and chronicity of ITP in children as AA genotype was higher in patients than controls and in chronic patients compared to those with newly diagnosed ITP.