Objectives. To determine whether there are demographic, clinical and radiological differences among patients with pulmonary tuberculosis (TB) and patients with TB and type 2 diabetes mellitus (DM2 + TB). Materials and methods. Observational retrospective cohort study. We compared the clinical characteristics of patients according to sex, age, time to sputum conversion to negative, presence of cavitation and the cure rate, duration of treatment and the proportion of change of treatment regimen, in patients with and without DM2 served by the Tuberculosis Control Program from 2010 to 2012 in the Rebagliati Healthcare Network of Lima, Peru. Results. 31 patients with TB+DM2 and 144 patients with TB were included. Differences (p<0.05) in the diagnostic method, the average of symptoms and the resistance pattern of TB among patients with and without DM2 were found. The presence of cavitation was more frequent in patients with TB + DM2. Having TB + DM2 delayed the time to sputum smear conversion to negative (RRa 4.16, 95% CI: 1.1-1.6) in the adjusted Cox regression analysis. Conclusions. There are differences in demographic, clinical and radiological characteristics in TB patients with and without DM2.The time to sputum conversion to negative is greater in patients with DM2.