Objective To investigate the prevalence of dental caries among college students and its influence on self-confidence, and to analyze the influencing factors of dental caries. Methods A questionnaire survey was conducted among 800 college students of Liaoning University from January to June 2025. The caries prevalence rate of the surveyed students was calculated. According to the presence of dental caries, they were divided into the occurrence group and the non-occurrence group. Univariate analysis and multivariate regression analysis were performed on the two groups to identify the relevant risk factors for dental caries, and to further understand the influence of dental caries on college students' self-confidence. Results Among the 800 surveyed college students, 245 developed dental caries, with a caries prevalence rate of 30.63%. Among the 245 students with dental caries, 135 (55.10%) believed that dental caries reduced their aesthetic self-confidence, and the other 110 (44.90%) believed that dental caries had no influence on their aesthetic self-confidence. There were no statistically significant differences in gender, grade, daily brushing frequency, or oral examination frequency between the two groups (P >0.05). There were statistically significant differences in major, drinking carbonated drinks/sugary drinks ≥5 times a week, brushing teeth after eating before bedtime, using the Bass brushing method, and using fluoride toothpaste between the two groups (P <0.05). Non-medical major, drinking carbonated drinks/sugary drinks ≥5 times a week, not brushing teeth after eating before bedtime, not using the Bass brushing method and not using fluoride toothpaste were all independent risk factors for dental caries among college students (P <0.05). Conclusion College students face higher risks of dental caries, and most college students believe that dental caries reduces their aesthetic self-confidence. Nonmedical major, drinking carbonated drinks/sugary drinks ≥5 times a week, not brushing teeth after eating before bedtime, not using the Bass brushing method and not using fluoride toothpaste are risk factors for dental caries among college students. In the future, it is necessary to strengthen oral health education for college students, enhance their oral health awareness and capabilities, and minimize the incidence of dental caries among college students.