Objectives: To determine the association between generalized anxiety disorder (GAD) and oral health problems, and to evaluate the mediating roles of sleep health using data from the 2023 Korea National Health and Nutrition Examination Survey. Methods: Data from 5,687 adults were analyzed using a complex sampling design. GAD was assessed with the GAD-7, oral health problems with self-reported chewing and speaking difficulties, and sleep health with mean sleep time and risk factors of obstructive sleep apnea. Mediation analyses were conducted using PROCESS macro Model 4 with covariate adjustment. Results: The GAD group had a higher mean chewing problem score than the group without GAD (2.13±0.03 vs. 2.05±0.03, p=0.021), while speaking problems did not differ (p=0.300). The GAD group had a shorter mean sleep time (6.57±0.03 vs. 6.70±0.03, p<0.001) and higher prevalence of snoring (21.2% vs. 18.0%, p=0.013) and daytime lethargy (36.8% vs. 20.2%, p<0.001). Sleep time (indirect effect = 0.002, 95% confidence interval [CI]: 0.001–0.004) and risk factors of obstructive sleep apnea (indirect effect = 0.005, 95% CI: 0.002–0.008) significantly mediated the association, indicating partial mediation. Conclusions: These findings underscore the importance of comprehensive sleep health assessment, particularly screening for risk factors of obstructive sleep apnea, in oral health management among individuals with GAD.