Purpose: This study aimed to identify factors related to problem drinking among freshman nursing students and to examine the relationship between drinking refusal self-efficacy and problem drinking. Methods: This descriptive correlational study was conducted with 130 freshman nursing students. Data were collected from April 4 to 14, 2023, using self-report questionnaires and analyzed using descriptive statistics, t-tests, ANOVA, Pearson correlation coefficients, and multiple regression. Results: The mean score for problem drinking and drinking refusal self-efficacy were 9.42±7.02 and 87.82±14.66, respectively. Problem drinking showed significant differences according to age and smoking status. Drinking refusal self-efficacy was negatively correlated with problem drinking (r=-.64, p<.001). Among the subdomains, social pressure showed the strongest correlation with problem drinking. Drinking refusal self-efficacy was identified as a significant predictor of problem drinking (β=-.60, p<.001), explaining 40.0% of its total variance (adj. R²=.40). Conclusion: Higher drinking refusal self-efficacy was associated with lower levels of problem drinking among freshman nursing students. These results suggest the need for intervention programs to improve drinking refusal self-efficacy and prevent problem drinking in nursing freshmen.