This study was undertaken to identify factors associated with unfavorable outcomes in patients with pulmonary tuberculosis (PTB) in Taipei, Taiwan in 2007-2008. Taiwanese adults with culture-positive PTB diagnosed in Taipei during the study period were included in this retrospective cohort study. Unfavorable outcomes were classified as treatment default, death, treatment failure, or transfer. Of 1616 eligible patients, 22.6% (365) had unfavorable outcomes, mainly death. After controlling for patient sociodemographic factors, clinical findings, and underlying disease, independent risk factors for unfavorable outcomes included advanced age, unemployment, end-stage renal disease requiring dialysis, malignancy, acid-fast bacilius smear-positivity, multidrug-resistant TB, and notification from ordinary ward or intensive care unit. In contrast, patients receiving directly observed treatment, and with a high school or higher education were significantly less likely to have unfavorable outcomes. This study advanced our understanding by revealing that a high school or higher education might lower the risk of an unfavorable outcome. Our results also confirmed the risk factors for unfavorable outcomes shown in previous research. Future TB control programmes in Taiwan should target particularly high-risk patients including those who had lower educational levels.