Psoas abscesses are suppurative collections within the fascia surrounding the psoas and iliacus muscles. In this retrospective study it was aimed to evaluate the demographic characteristics, clinical and laboratory findings and treatment outcomes of 15 psoas abscess cases admitted to Baskent University Hospital, Ankara, Turkey during June 2003-January 2008 period. The mean age of the patients was 55.8 years (range 18 to 70 years) with a female to male ratio of 5/10. Thirteen of the cases (86.5%) were admitted with the complaints of fever and back pain. Thirteen of the cases were diagnosed by abdominal computerized tomography while the other two by abdominal ultrasonography. One of the 15 patients was considered as primary psoas abscess, while the remaining 14 as secondary psoas abscess. The most common accompanying disease was diabetes mellitus (66.6%). Fourteen patients with secondary psoas abscess had vertebral osteomyelitis which was due to tuberculosis in five cases, to urinary tract infection in five cases, to pneumoniae in two cases, to surgical infection in one case and to brucellosis in one case. The cultivation of the abscess material from the 14 secondary psoas abscess cases revealed growth of bacteria in 11 of them (5 Mycobacterium tuberculosis, 1 Escherichia coli, 1 methicillin-sensitive Staphylococcus aureus, 1 methicilin-resistant S. aureus, 1 Acinetobacter baumannii, 1 Brucella melitensis, 1 Serratia marcescens). The biochemical parameters of the cases (mean leukocyte counts: 14.500 cell/mm3; mean erythrocyte sedimentation rates: 78 mm/hour; mean C-reactive protein levels: 108 mg/dl) were also high. Thirteen patients underwent percutaneous drainage and received appropriate antibiotic treatment and the other two patients were treated with open surgical debridement. The duration of antimicrobial treatment was one year for M. tuberculosis cases and about 4-6 weeks in the others. One of the cases died due to complicating meningitis and sepsis. It is remarkable that in our series none of the psoas abscess cases were secondary to the diseases of the digestive tract unlike the series indicated in the literature. The isolation of M. tuberculosis as the causative agent in 5 (33.3%) cases emphasizes the fact that tuberculosis is still an important public health problem in Turkey.