Objetive: To determine the impact of dental erosion on the oral health related quality of life in preschool children aged 3 to 5 years. Material and Methods: An observational, cross-sectional study was carried out. The sample consisted of 150 preschoolers from a preschool in the suburban areas of Lima, Peru. The Basic Erosive Wear Examination (BEWE) index was used for the evaluation of dental erosion; and the Early Childhood Oral Health Impact Scale (ECOHIS) was used to measure quality of life. The data were analyzed in the statistical program SPSS v.25. Results: A prevalence of erosion of 40.7% was observed; with an initial loss of tooth surface in 28% and a loss of hard tissue of <50% of the surface area in 12% of the examined children. No statistically significant association was found between the impact of erosion and the oral health related quality of life (p> 0.05). However, the dimension with the highest score was functional limitations. Conclusion: The prevalence of dental erosion in preschool children was high, and dental erosion did not show an impact on the oral health related quality of life.