Nephrotic syndrome (NS) is considered as a common chronic disorder. Its prevalence in children is 15 times greater than adults. RANKL is one of proteins in the tumor necrosis factor (TNF)/TNF receptor families required for the control of bone remodeling. The aim of this study was to assess the serum level of RANKL in children with idiopathic nephrotic syndrome (INS) treated with glucocorticoids and its relation to the different stages of the disease (remission & relapse) all compared to normal children. The study comprised 40 children diagnosed as having INS. Twenty children were in relapse and the other 20 were in remission. Another 20 healthy children served as control group who were matching in age and sex involved in the study. They were screened for their anthropometric measurements (height, weight, Body mass index (BMI) for-age Z-score), clinical parameters and laboratory assessment (serum RANKL, Albumin, cholesterol, A/c ratio, calcium, phosphorus, ALP, urea, creatinine). Results of this work revealed that sRANKL concentration was significantly higher in relapse group as compared to control group (p=0.002). No similar difference was noted between remission and control. Also results showed a significant positive correlation between duration of glucocorticoids (GCS) treatment and concentration of sRANKL in both groups of NS patients. It was concluded from this study that treatment with GCS for long time results in bone affection so sRANKL can be used as a detector of bone affection and abnormality and accordingly early intervention and prevention of complications can take place.