The incidence of breast tuberculosis in the world is very low. This pathology can be primary and, more commonly, secondary. It is presented as an extrapulmonary focus due to Mycobacterium tuberculosis invasion in the mammary gland. Method: we present the clinical case of a 29-year-old in AIDS woman a breast tumor. At the time of the consultation, rales were also heard in both pulmonary fields. A chest x-ray, blood analysis, and computed tomography of breast tumor and armpit, were performed. One month after admission to the hospital, the tumor fistulized and drained purulent secretion spontaneously. A sample was taken and sent to anatomopathological and microbiological analysis A tuberculin skin test (PPD) was also performed. ouch. the chest X-ray showed a diffuse interstitial infiltrate, suggestive of Pneumocystis Jirovecci pneumonia. Computed tomography of the breast and armpit tumors reported the presence of multiple adenopathies. The PPD value reported was 5 millimeters; this rate is considered as a positive reaction in HIV patients. The result of the pathological anatomy for neoplasic cells was negative. The microbiological results were: Mycobacterium tuberculosis, sensitive to Isoniacid, Streptomycin, Pyrazinamide, Ethambutol and Rifampicin. Based on the results of the laboratory report, the diagnosis was pulmonary and mammary tuberculosis. The pulmonary tuberculosis in AIDS patients, can give non-characteristic radiographic images. This case proved how the diagnosis could be confused with pneumonia by Peumocystis jirovecci in a first appr