OBJECTIVE: To analyze the dietary quality of adults and to identify associated factors. METHODS: Cross-sectional study carried out in a sample of adults (n=195), aged 20-50 years, of both genders, from a population-based study in Cuiabá, Mato Grosso, Brazil. Food consumption data was collected by a food frequency questionnaire. Sociodemographic, lifestyle, anthropometric, and body composition data were also collected. Diet quality was analyzed by the Brazilian Healthy Eating Index-Revised. The associations were estimated by Poisson regression. RESULTS: The mean Brazilian Healthy Eating Index-Revised score was 75.2 points (CI95%=74.2-76.1), which differed significantly between the genders (p=0.03). Women had higher scores for whole fruit and sodium (p<0.01), while men had higher scores for oils, nuts, and fish fat (p=0.02). Individuals aged >30 years had higher total Brazilian Healthy Eating Index-Revised score and higher scores for the groups whole fruit; saturated fat; and calories from solid fats, alcoholic beverages, and added sugar (p<0.01). The Poisson regression between high Brazilian Healthy Eating Index-Revised and the independent variables showed that high Brazilian Healthy Eating Index-Revised was associated with being female, being aged 30 years or more, and being from families whose household head had 8 or more years of formal education. CONCLUSION: The factors associated with high Brazilian Healthy Eating Index-Revised were age, gender, and education level of the household head.