Crossed renal ectopia is a rare urinary system anomaly which mostly is asymptomatic and is diagnosed incidentally. Urinary obstruction, infection, and neoplasia of the urinary system and nephrolithiasis are main complications of this anomaly. A 6-year-old boy admitted to the hospital with colicky abdominal pain and nausea. Abdominal examination revealed tenderness in right lower quadrant. Urine analysis and culture were normal. Kidney ultrasonography showed right kidney in pelvis cavity with no kidney tissue in left side. TC 99-DMSA scan demonstrated no radiotracer accumulation in the normal renal area. Radiotracer accumulation was seen in the pelvis area with a deviation to the left. Voiding cystoureterogram revealed right sided grade II vesicoureteral reflux. Severe urological anomalies in children may be asymptomatic or have nonspecific symptoms such as abdominal pain.