In this study, we analyzed the number of TB cases in an emergency room (ER) and the susceptibility profile of Mycobacterium tuberculosis strains. Patients were selected from among those treated at the Hospital das Clínicas, in the city of Belo Horizonte, Brazil. Between 2002 and 2005, 240 TB patients were identified. Of those, 117 patients (48.7%) were diagnosed in the ER, 72 (61.5%) presenting positive sputum smear microscopy. Drug susceptibility testing was carried out in 90 strains, of which 80 (89%) were sensitive, 9 (10%) were resistant, and 1 (1%) was multidrug resistant. The incidence of positive smear sputum microscopy and resistant TB strains was high, which calls for the immediate adoption of TB control measures in the ER.