The aim of the present study was to evaluate the prevalence and impact of malocclusion on oral health-related quality of life (OHRQoL) among schoolchildren aged 8 to 10 years and their parents in Diamantina, a town in the southeast of Brazil. A cross-sectional study was conducted with a sample of 390 randomly selected children who were subjected to a clinical oral examination. The Dental Aesthetic Index was used to diagnose malocclusion and the need for orthodontic treatment. The Child Perceptions Questionnaire (CPQ (8-10)) was used to evaluate the impact of malocclusion on OHRQoL. The children's parents answered the Brazilian Economic Criterion Questionnaire for the socioeconomic classification. Data analysis involved the nonparametric Kruskal-Wallis test and Spearman's correlation coefficients. The variables were grouped into a hierarchy of categories ranging from distal to proximal determinants. Poisson regression analysis with robust variance was performed at each level to correlate the total CPQ (8-10) score with the independent variables. The prevalence of malocclusion was 78.7%. Crossbite remained significantly associated with a negative impact on OHRQoL (PR = 1.28; 95%CI:1.17-1.39; p < 0.001). The prevalence of malocclusion was high in the sample investigated and exerted a negative impact on OHRQoL.