Objectives: This study aimed to explore the relationship between mental health factors and oral diseases in Korean adolescents, thereby providing foundational evidence to support mental well-being and promote oral health. Methods: Using data from 54,653 adolescents who participated in the 20th Korea Youth Risk Behavior Survey in 2024, statistical analysis was performed using SPSS 21.0 to examine the relationships among general participant characteristics, mental health factors, and oral health outcomes. Results: Mental health problems, including inadequate recovery from sleep, loneliness, sadness, hopelessness, and suicidal ideation, were more common among females, high school students, adolescents with lower socioeconomic status, those with a history of drinking or smoking, and those with poor perceived health (p<0.001, p<0.01). These mental health factors, along with stress, were significantly associated with an increased risk of developing oral pain (p<0.001). Suicidal ideation was also significantly associated with both types of oral pain, with stronger effects observed for gum pain (p<0.05, p<0.001). Conclusions: Adolescents’ mental health significantly correlated with their oral health status. Early screening and intervention for vulnerable groups is crucial, and the establishment of integrated youth-centered programs and policies that connect mental health and oral care within the family, school, and community environments is highly recommended.