Diagnosis and management of psoas abscess is usually delayed as it is a rare entity in childhood period. Mortality is seriously high in case of delayed diagnosis and inappropriate therapy. We herewith present a female patient who was admitted with the symptoms of pain on the right side and legs, difficulty in walking and high fever. She was hospitalized with presumed diagnosis of perirenal hematoma, but finally diagnosed as psoas abscess secondary to urinary tract infection by the help of invasive techniques. We would like to emphasize the paramount importance of appropriate radiology methods in order to diagnose and treat the psoas abscess. ©2006, Fırat Üniversitesi, Tıp Fakültesi