Objective: To determine the association between diabetes mellitus and chronic depression in adults in the Peruvian population. Materials and methods: A quantitative, observational, cross-sectional and correlational study was carried out, based on the data collected by the 2020 Encuesta Demográfica y de Salud Familiar (ENDES – Demographic and Family Health Survey, 2020). The sample was made up of 14,245 adults; depression was considered as a dependent variable (with depression/without depression), and the independent variables were diabetes mellitus (Yes/No), wealth index (the poorest, poor, middle class, rich, the richest), education (kindergarten-preschool and primary, secondary, non-university higher, university higher and graduate), alcoholism (Yes/No), area of residence (urban/rural). The program used for the statistical analysis was IBM SPSS: Release 23. A univariate data analysi...