Background: The pelvicalyceal system distension and dilatation are referred to as hydronephrosis. Objective: The goal of the current study was to use ultrasonography to identify newborns and young children at risk for renal scarring and assess whether they would require additional surgical intervention. Subjects and Methods: This retrospective study was conducted from January 2008 to February 2012 and comprised 320 infants and newborns, who were diagnosed with hydronephrosis by US standards (200 boys, 62.5%; 120 girls, 37.5%), unilateral or bilateral. 130 of them were newborns, and 190 were kids. An algorithm for managing and treating hydronephrosis based on the Society of Fetal Urology (SFU) grading system for US can be created. Further imaging tests such as voiding cystourethrogram and isotope scanning were applied. Results: Using the SFU grading system, 150 patients (46.8%) were classified as I and II-degree hydronephrosis and 170 cases (53.2%), as III- and IV-degree hydronephrosis. Without any risk of UTI, Grade I and II spontaneously cleared (P <0.001). With a significant risk of recurrent UTI, all 170 instances of hydronephrosis in grades III and IV required isotope scanning and a voiding cystourethrogram (P <0.001).  Conclusions: It could be concluded that the SFU grading system developed by the US is a helpful diagnostic tool for hydronephrosis.