Background: Nephrotic syndrome (NS) is one of the commonest chronic renal diseases in children, characterized by selective proteinuria, hypoalbuminemia, hyperlipidemia, and edema. This study aimed to assess the level of serum immune globulin (E) in children with idiopathic nephrotic syndrome as marker for prognosis of therapy. Methods: This prospective study was conducted in the pediatric department, Benha University Hospital. The study consisted of two groups: Group I: Fifty children suffering from idiopathic nephrotic syndrome treated with corticosteroid. Group II: Fifteen healthy children as a control group. All included children were subjected to full history taking, complete clinical examination, and laboratory assessment as complete blood count (CBC), absolute eosinophilic count, serum urea & creatinine, serum level of IgE, electrolytes, and 24 h protein in urine. Results: About three-quarters of group I were steroid sensitive (72.0%), and one-quarter were steroid-resistant (28.0%), Median serum IgE was significantly higher in group I (275.55) than group II (100.5), P= 0.001. Median serum IgE was significantly higher in the steroid-resistant group (911.85) than the steroid-sensitive (164.5), p=0.001. Roc analysis was done for differentiating between nephrotic patients and controls. For IgE, it revealed a significant area under curve (AUC) of 0.788. Conclusion: A significantly higher serum IgE levels were associated with Nephrotic syndrome and more prominently in patients with steroid-resistant nephrotic syndrome (SRNS).