The aims of this study were to identify dietary patterns (DPs) of children and adolescents participating in three cross-sectional surveys (2013-2015) and to test their associations with sociodemographic variables, physical activity (PAS), screen-based sedentary activity (SA), and weight status. One-day data were obtained from 5,364 schoolchildren (7-12 years) from public schools of Florianopolis (South of Brazil), using the validated questionnaire Web-CAAFE (Food Intake and Physical Activity of Schoolchildren). DPs were derived from the frequency of daily consumption of 32 foods/beverages by latent profile analysis. Multinomial logistic regression analysis was used to estimate the association of the DPs with sociodemographic variables, physical activity, screen activity and weight status. 'Traditional', 'Monotonous', and 'Mixed' DPs were identified. The percentages of children and adolescents within these profiles were 41.3, 36.3, and 22.4%, respectively. Children and adolescents in the highest tertiles of both PAS and daily frequency of SA had a higher probability to present a 'Mixed' DP compared to peers with less PAS and SA. Children and adolescents who reported having a school meal were significantly more likely to present the 'Traditional'DP, while boys who did not report having a school meal had a higher probability to present the 'Monotonous' DP. The DPs were not associated with the year of survey, age, family income, or weight status.