Pulmonary tuberculosis (TB) is an endemic infectious disease in Taiwan. A retrospective study was conducted to define clinical manifestations and outcomes of patients with pulmonary TB among hematopoietic stem cell transplantation (HSCT) recipients. We identified eight out of 350 HSCT recipients as having pulmonary TB over a 6-year period. The relative risk of having pulmonary TB after HSCT was 13.1-fold higher than in the general population. There was a trend toward increased risk of having pulmonary TB in allogeneic HSCT as compared to autologous HSCT (4.8 +/- 1.8% vs 0, P = 0.067). All the eight patients with pulmonary TB received allogeneic HSCT and most (seven of eight patients) developed the infection during treatment for GVHD. Computed tomography of the chest was normal in one patient, with the rest showing either interstitial (two patients) or alveolar infiltrates (five patients) at the onset of pulmonary TB. The four fatal cases had an obviously shorter duration between HSCT and onset of infection. Our data suggest that pulmonary TB in HSCT recipients is not uncommon in this endemic area. Therefore, an effective strategy of prophylactic treatment for candidates and recipients of allogeneic HSCT, who may have latent pulmonary TB infection, must be developed.