The incidence of urolithiasis in children has been steadily increasing in developed countries mainly due to changes in dietary habits. The occurrence of symptoms suggestive of urolithiasis in children with urinary solute abnormalities predisposing to stone formation but with normal renal ultrasound and X-ray plain film is approximately 9 times higher than the occurrence of overt stone disease. This discrepancy may depend on several factors, for example: the limited sensitivity of these methods of imaging, the presence of urinary crystals that, while not detectable with imaging, injure bladder epithelium, in addition to imaging studies performed after the passage of calculi giving negative results. Correct technique during urine collection is also essential for diagnosis. Urolithiasis must be suspected in the face of abdominal pain even central or diffuse pain in younger children when there is a positive family history even though specific urinary symptoms such hematuria and dysuria may be lacking.