Background: the Mediterranean diet has been associated with a lower prevalence of obesity and metabolic syndrome, and with healthier lifestyles in adults and children, but data is scarce in younger ages. The Mediterranean -type ecosystem of the central region of Chile as well as its traditional gastronomy would facilitate the adoption of this dietary pattern. Objectives: to assess the adherence to Mediterranean diet in preschoolers and their parents, and to evaluate the impact of a nutrition education intervention and diet implementation. Methods: prospective cohort study. The KidMed index was applied to children older than 18 months, and the Mediterranean Dietary Index in Chile (Chilean-MDI) to their parents, before and after a remote educational intervention. Results: one hundred and thirty-nine families participated, with 95 preschoolers; 56 % were girls, aged 26.2 +/- 8.7 months. The basal mean KidMed score was 7.4 +/- 1.9 and increased to 7.9 +/- 1.9 after the intervention (p = 0.1). The Chilean-MDI score was 6.9 +/- 1.8 and 7.1 +/- 1.7, respectively (p = 0.09). When separated by categories, there was improvement from low and moderate adherence to optimal adherence in both children and their parents (Chi2, p = 0.009 y p = 0.04). In 58 dyads, there was a positive correlation between the KidMed and the Chilean-MDI index, pre- and post -intervention (Pearson R = 0.3 y 0.34; p = 0.004 y 0.003, respectively). Conclusions: most of these sample of preschoolers and their parents had a moderate adherence to Mediterranean diet, with an improvement after an educational intervention.