Tuberculosis has been increasing especially in urban areas and in immunosuppressed patients; however, the incidence and factors associated with tuberculosis in OLT patients are unknown. Five of 550 patients who underwent OLT at the Mount Sinai Medical Center during a 5-year period were noted to have tuberculosis. The mean age of the patients was 49.2 years; there were 3 males and 2 females and 3 were foreign born. One of 5 had a prior history of tuberculosis. Tuberculin skin tests performed before transplant revealed 1 positive and 2 anergic reactions. The preoperative chest x-ray revealed apical fibrosis in 2 patients and bilateral apical disease with a nodule in 1 patient. Tuberculosis developed from 2 to 57 months after surgery in 4/5 patients. One had miliary lesions of the peritoneum discovered at the time of OLT. One patient had recent contact with a patient with pulmonary tuberculosis. At presentation, fever was present in 4 of 5 patients, pulmonary lesions in 3 patients, meningitis in 2; during hospitalization, 1 had a liver abscess and disseminated intravascular coagulation and peripheral gangrene. Lymphocytosis was noted in the pleural (1), peritoneal (1), and cerebrospinal fluid (1). Acid-fast smears were positive in bronchoalveolar lavage fluid (1), peritoneal isolates (1), and liver biopsy (1). All patients had positive cultures for Mycobacterium tuberculosis. These isolates were all sensitive to isoniazid, streptomycin, rifampin, ethambutol, and pyrazinamide. Four of 5 patients were treated with isoniazid and rifampin, 2 received pyrazinamide, 2, amikacin, 2, ofloxacin, and 2, ethambutol. Three of 5 patients are doing well on antituberculous therapy and 2 expired with tuberculosis as the cause of death. In OLT patients with unexplained fever, tuberculosis including extrapulmonary and disseminated disease should be considered since the mortality rate is very high. Liver transplantation can be performed in the presence of active peritoneal tuberculosis with the use of judicious antituberculous therapy. The role of preventive therapy is controversial, though use in certain high risk patients is suggested.