Introduction: The aim of the study was to evaluate the impact of social risk factors on treatment outcome among culture- positive patients treated for active pulmonary tuberculosis in three separate districts—Warsaw, Gdansk and Siedlce—in years 1995 and 2000. Materials and methods: We retrospectively reviewed medical records of patients who were notified in 1995 and 2000 and were treated in hospitals and dispensaries. Alcohol abuse and homelessness were recognized as risk factors associated with tuberculosis and nonadherence to treatment. Treatment outcome was evaluated using treatment indicators defined by the World Health Organisation: cured, treatment completed, treatment defaulted, treatment failure and “other” results of treatment. Results: Seven hundred and eight patients with culture positive pulmonary tuberculosis were included (373 in 1995 and 335 in 2000). There were 85 patients with risk factors in 1995 and 101 patients in 2000. 80 of participants in 1995 and 69 in 2000 abused alcohol, 5 and 32 were classified as homeless, respectively. Among alcohol abusers treatment success rates according to the WHO definition (either bacteriologic cured or treatment completed) were 45.1% in 1995 and 53.6% in 2000. Among patients not abusing alcohol treatment success rates were 63.8% and 54.1%, respectively. The differences were statistically significant (p = 0.005 in 1995 and p = 0.0186 in 2000). In 1995 forty percent of homeless patients had succeeded treatment, while the rate of treatment success among non-homeless was 60%. Because of small number included in homeless group the difference was not statistically significant (p = 0.6532). In 2000 treatment success rate among homeless participants was 25% and among non-homeless—57.1%, which was highly statistically significant (p = 0.001). Conclusions: Alcohol abuse and homelessness were associated with bad treatment outcome among patients with pulmonary tuberculosis. Interventions to improve treatment adherence in patients considered to be at risk for default are necessary.