Objectives: This study aimed to identify factors related to oral health and depression in Korean adults and contribute to the development of a mental health program to improve depression through oral health management. Methods: Data was obtained from the 2021 Korean Community Health Survey. The chi-square test was used to determine the differences in depression experience relative to general participant characteristics and their oral health. To determine the odds ratio and 95% confidence interval, multiple logistic regression analysis was used. All statistical analyses were performed using the SAS software (version 9.4). Results: The results suggest that depression may be influenced by gender, age, household generation, drinking habits, subjective health level, moderate to high exercise, breakfast, high blood pressure, diabetes, subjective oral health level, chewing discomfort, and tooth brushing. An increasing level of depression was associated with decreasing subjective oral health level (1.34 times), uncomfortable chewing (3.08 times), and frequency of toothbrushing after lunch or before going to bed (1.23 times and 1.58 times, respectively). Conclusions: Our study confirmed a close relationship between oral health and mental health. In developing health programs for improving depression, appropriate oral health care should be considered.