Background:Nephrotic syndrome is a common pediatric kidney condition t. It happens in young children and adolescents. The goal of this research was to investigate the diagnostic value of urinary MCP-1 in pediatric patients with idiopathic nephrotic syndrome. Methods: At the pediatric nephrology outpatient clinic and the pediatric nephrology unit, this casecontrol study was carried out at Zagazig University hospitals on children attending at pediatric inpatient and outpatient clinics. They were divided into three groups: group A, which consisted of 27 nephrotic patients in remission; group B, which consisted of 27 nephrotic patients who were active and experiencing either their first attack or relapses; and group C, which consisted of 27 sex- and age-matched healthy children who were present at a general pediatric clinic. Results: There is a statistically significant difference in urinary monocyte chemotactic Protein 1. The best cutoff of urinary monocyte chemotactic protein 1 in the diagnosis of nephrotic syndrome is ≥79 with the area under curve 1, sensitivity 100%, specificity 96.3%, positive predictive value 98.2%, negative predictive value 100%, and overall accuracy 98.8%. The best cutoff steroid-resistant nephrotic syndrome by using urine monocyte chemotactic protein 1 as a diagnostic marker is ≥512 with area under curve 0.992, sensitivity 96.3%, specificity 88.9%, positive predictive value 89.7%, negative predictive value 96%, and overall accuracy 92.6%. Conclusions: The findings imply that urine MCP-1 levels can differentiate between patients with active disease and those who are in remission, as well as between cases of steroidresistant nephrotic syndrome and cases of steroid-sensitive nephrotic syndrome.