Objectives: To determine how the oral health evaluation index and oral health-related knowledge, behaviors, and perceived symptoms influence the oral health related quality of life (OHRQoL) of older people aged 65 to 85 years. Methods: Data were collected from 210 older people between June 8 and July 9, 2023. Descriptive statistics, t-tests, one-way analysis of variance, Pearson’s correlation analysis, and multiple regression analysis were performed using SPSS Statistics version 22.0. Results: There were significant differences in the oral health evaluation index, oral health knowledge, and behaviors according to general characteristics such as age and denture status. Correlation analysis identified positive relationships between the oral health evaluation index, behavior, symptoms, and OHRQoL. Multiple regression analysis identified the oral health evaluation index (β=0.443, p<0.001) and oral health behavior (β=0.118, p<0.05) as significant predictors of OHRQoL. Conclusions: Strengthening oral health behaviors through targeted programs is essential for improving the OHRQoL of older people.