Psoas abscess is a rare disease with various etiologies. The most common pathogen in primary abscess is Staphylo coccus aureus. Crohns disease is the most common cause of secondary abscess. Mycobacterium tuberculosis is considered an extremely rare cause of psoas abscess, The clinical manifestation is insidious, the classic symptoms are pain and fever. Computed tomography (CT) is the gold standard in the diagnosis and follow-up of retroperitoneal abscesses. The treatment of choice is percutaneous drainage guided by imagery. Surgical drainage should be reserved for cases of failure of percutaneous drainage, if possible via the extraperitoneal route, but in the event of a secondary abscess, the transperitoneal approach is preferred to correct the original disease.