Objectives: This study aimed to examine the mediating effect of health literacy on the relationship between generalized anxiety disorder (GAD) and problems with oral function among postmenopausal women in Korea. Data were obtained from the 2023 Korea National Health and Nutrition Examination Survey (KNHANES). The findings will inform strategies to enhance health literacy and promote sustainable oral health management. Methods: Data were obtained from the 2023 KNHANES, which was first year to include a health literacy index. Participants were divided into groups based on GAD status. Complex sampling analysis was conducted using IBM SPSS Statistics 21.0, and the PROCESS macro. Model 4. was applied to test the direct, indirect, and total effects of health literacy on the relationship between GAD and oral health problems. Results: After controlling for sociodemographic characteristics and comorbidities, health literacy was found to have a statistically significant mediating effect on the relationship between GAD and both chewing and speaking difficulties. Conclusions: GAD in postmenopausal women was associated with decreased oral function, and health literacy played a mediating role in alleviating this negative effect. It is recommended that oral health education programs that improve both anxiety management and health literacy are developed and implemented.