Leprosy and tuberculosis are endemic in several countries. The aim of this study was to describe factors associated with co-infection among both diseases. A systematic review was carried out, following the Quality of Reporting of Meta-analyses, with the PubMed and Biblioteca Virtual em Saúde (BVS) portals as sources, under eligibility criteria: cross-sectional, cohort, case-control studies or case reports, published in Portuguese, English, French and Spanish, from 2015 to 2020. Studies that dealt with leprosy and tuberculosis not in the context of co-infection were excluded. The initial phase resulted in 1079 articles; 13 went on to a final stage. All were case reports. Thirteen (72.2%) participants were male, aged between 17 and 72 years. Life habits were found in 8 (44.4%) of the articles: 1 (12.5%) reported chronic alcoholism, 1 (12.5%) reported chronic smoking and alcoholism and 1(12.5%) reported chronic smoking, alcoholism and use of illicit drugs. Pathological history was mentioned by 14 (77.8%) patients; 1 (7.1%) reported HIV/AIDS. Three patients (16.6%) described previous history of tuberculosis and/or leprosy. Seven (38.9%) participants reported vaccination with Bacillus Calmette-Guérin. The pulmonary form of tuberculosis predominated and one third of the patients presented resistance to, at least, one tuberculostatic. All cases had multibacillary leprosy. The study did not highlight any comorbidity, and there was no change in the course of the conditions owing to co-infection.