A 12-year-old girl was admitted for abdominal pain and signs of acute kidney injury. Physical examination showed abdominal distension and a tumefaction in the lower abdomen. Laboratory and clinical findings were consistent with acute kidney injury. Abdominal ultrasonography showed an oval mass, which corresponded with hematometrocolpos, and right-sided hydronephrosis. Catheterization followed by cruciate hymenectomy was performed. The patient recovered completely. Imperforate hymen is an obstructive anomaly of the female reproductive tract of unknown etiology that can cause a variety of symptoms. It is a rare, but possible cause of acute kidney injury. Patient history data and genital examination findings are sufficient to establish the diagnosis. Abdominal ultrasonography is the most useful diagnostic modality.