Background: The purpose of this study was to analyze the relationship between parental perceptions of maintaining oral hygiene with the condition of oral hygiene down syndrome in the Surabaya area. Materials and Methods: This type of research is quantitative analytic observational with a cross-sectional design. Respondents involved were 100 parents with down syndrome and 100 children with Down syndrome. Data collection used a questionnaire instrument to measure parental perceptions of Down syndrome and dental examination sheets to measure oral hygiene conditions for down syndrome. Data analysis used the Spearman correlation test. Results: Parental perception of down syndrome shows the same percentage of high and low scores (50%). Most oral Hygiene down syndrome conditions show a low value (54%). Spearman analysis showed a significant relationship between parents' perceptions of Down syndrome and the condition of oral hygiene down syndrome with a negative correlation (p-value = 0.000; r = -0.586). Conclusion: The level of parental perception of down syndrome is significant with the condition of oral hygiene down syndrome.