Background:
Since e-cigarette was introduced into the global market, its use has become popular especially among young adults. But little is known about the prevalence and associated factors of e-cigarette use among young adults in Korea. The purpose of this study is to identify the factors associated with ever-use of e-cigarette among Korean college students.

Methods:
A survey to collect the data for this study was distributed to 550 students in 5 universities in S city and K city from October to December 2016. Data from the survey which consists of self-reporting questionnaires were analyzed using binary logistic regression analysis. Ever-use of e-cigarette was assessed by asking "Have you ever used an e-cigarette?" (yes/no). The final sample for this study (n=399) included those who had ever heard of e-cigarette.

Results:
Among 399 students who had ever heard of e-cigarette, 68(17%) were e-cigarette ever-users. E-cigarette ever-use was higher among male students(OR=6.82, 95% CI=2.02, 23.02, p< 0.05), students living in dormitory(OR=10.19, 95% CI=1.16, 89.49, p< 0.05), whose father is a smoker(OR=58.41, 95% CI=8.70, 392.39, p< .001), who have the experience of past 2-week binge drinking(OR=43.78, 95% CI=5.61, 341.93, p< .001) and past 30-day cigarette smoking(OR=1.02, 95% CI=1.01, 1.03, p< .001).

Conclusions:
This study showed significant association between e-cigarette ever-use and gender, residence type, father's smoking status, past 2-week binge drinking and past 30-day cigarette smoking. Associated factors of e-cigarette use should be considered for smoking prevention program for college students. To better understand the patterns and determinants of e-cigarette use among young adults in Korea, further studies are needed.