PURPOSE: The purpose of this study was to assess alcohol and caffeine intake and identify the impact of alcohol and caffeine intake on body mass index, alcohol use disorder, and quality of sleep among university students. METHODS: This study design was accomplished with a cross sectional survey and conducted from May to June 2014. One hundred and twenty-four freshmen of E university in S city, Korea were selected and evaluated by self-administered questionnaires. Alcohol and caffeine intake were measured by self-reported recall. The data were analyzed using descriptive analysis, independent t-test, one-way ANOVA, Pearson's correlation, and multiple linear regression. RESULTS: The average amount of alcohol intake was 175.02 +/- 219.97 g and the proportion of freshmen who took in more than 40g per day of alcohol was 75%. The average amount of caffeine intake was 116.79 +/- 111.14 mg. Factors influencing alcohol use disorder were dwelling type (t=2.25, p=.027) and alcohol intake (t=8.11, p<.001). And, the factor influencing quality of sleep was caffeine intake (t=3.88, p<.001). CONCLUSION: In order to reduce the harmful drinking of university students, preventive activities for freshmen are required and efforts on the part of the school needed.