Patients with diabetes mellitus (DM) are at greater risk of developing active tuberculosis and other intracellular bacterial infections, although the risk of acquiring infections from nontuberculous Mycobacterium (NTM) remains undefined. This study evaluated associations between DM and incidence of NTM infection-caused pulmonary and cutaneous diseases. Data for DM patients were extracted from the National Health Insurance Research Database of Taiwan. The DM cohort included 136,736 patients, and cases were matched randomly by age, gender, and index year with non-DM patients. Multivariate Cox proportional hazards regression was used to calculate adjusted hazard ratios of incident NTM-caused diseases in the DM cohort compared with non-DM control subjects. The frequency of incident NTM-caused diseases was significantly greater in DM patients (0.12%) than in non-DM patients (0.08%) (P < 0.05), including patients with type 1 DM (0.12%) and type 2 DM (0.12%) (all P < 0.05). Adjusted multivariate Cox regression analysis revealed that the incidence of NTM-caused diseases in DM patients was 1.43-fold greater than that in non-DM patients overall (P < 0.05), particularly in pulmonary (1.13-fold), other specific (excluding pulmonary, cutaneous, and disseminated diseases; 3.88-fold), and unspecific (atypical NTM infection; 1.54-fold) diseases (all P < 0.05). In conclusion, both type 1 DM and type 2 DM patients have high risk of NTM-caused diseases, suggesting that physicians need to pay more attention to this issue concerning the high risk of NTM-caused infection in DM patients.