Drug abuse is related to many medical complications, which depend on the drug type, dose injected, the method of delivery and site of injection. We report a case of psoas abscess in young heroin addict, HIV negative, who was admitted in Emergency Center of Clinical Center in Belgrade because of fever, anaemia, prostration and right groin pain. Clinical and radiological examination were performed. CT showed large abscess of the right psoas muscle, 12 x 4 cm large. Treatment included percutaneous drainage and administration of iv antibiotics. There is regression of inflamation. At discharge patient was in good condition without signs of infection.