Background: A urinary tract infection (UTI) is an infection that affects part of the urinary tract. When it affects the lower urinary tract it is known as a simple cystitis (a bladder infection). Ultrasound is a non-invasive test that can demonstrate the size and shape of the kidneys, the presence of duplication and dilatation of the ureters and the existence of gross anatomic abnormalities.Aim of the study: The aim of the study is to estimate the value of ultrasound in detecting urinary tract anomalies and to compare between ultrasound,voiding cystourethrography and dimercaptosuccinic acid scan.Methods: This study was conducted at the Nephrology clinic , New Children’s Hospital, Faculty of medicine, Cairo University; from August 2012 to March 2013, where a total 30 children were presenting with first attack of acute febrile UTI . All patients were subjected to Laboratory investigations: Urine analysis, urine culture and sensitivity with colony count, blood urea nitrogen (BUN), serum creatinin, complete blood count (CBC), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). Renal ultrasound, voiding cystourethrogram and dimercapto-succinic acid scan. Results: Sixteen (53.33%) of the patients were females and fourteen of them (46.6%) were males. All the studied patients had fever with a mean of 38.96±0.44, the mean duration of illness was 6.23±5.64 days. All studied patients subjected to ultrasound examination, 19 of the studied patients had an ultrasound abnormality suggesting VUR and they represented about 63.3% of the studied patients. The commonest US abnormalities found in our study were kidney stones (15.8%). Only two patients who had abnormal ultrasound had also vesicoureteric reflux on voiding cystourthrography (VCUG). Sensitivity of ultrasound 66.7%, specificity 37.5% , positive predictive value (PPV) 21.1% ,negative predictive value (NPV) 81.8% & total accuracy (TA) 43.33%. Conclusion: We concluded that ultrasound alone was not of much value in diagnosing and putting a plan of first attack of febrile urinary tract infection.