OBJECTIVE: The present study sought to determine the relationship between the level of oral health knowledge of parents and the oral hygiene of their preschool children in the AAHH Puerto Morey - Belen; in the year 2024. METHOD: The study was conducted using a quantitative approach. It was a non-experimental, cross-sectional, and correlational design. The sample consisted of 139 preschool children, aged between 2 and 6 years, residing in the AAHH Puerto Morey in the district of Belén. A questionnaire on oral health knowledge was administered to the parents, and the IHOS was used to assess the oral hygiene status of their children. RESULTS: It was found that the highest percentage of parents have an average knowledge of oral health, accounting for 79.9% of the total sample, while the IHOS results indicated that the children have good oral hygiene, with the highest percentage being 53.2%....