Background Electronic cigarettes (e-cigarettes) are sold in France since 2010 and have rapidly become popular. However, factors associated with e-cigarette use among young adults are not well known. Methods We used data from the 2015 French TEMPO community based cohort study, restricted to current and former smokers with data on e-cigarette use (n=368 adults, 23-41 years). Participants completed a self-administered questionnaire including information on family status, educational attainment, occupation and type of work contract, health problems, alcohol and cannabis use, electronic cigarette use, as well as perceptions of e-cigarettes. Use of traditional tobacco was assessed in 2011 and 2015. Data were analyzed using logistic regression models. Results Among current and former smokers, 26.9% reported lifetime e-cigarettes use and 15.2% current use. Factors associated with lifetime use were: low socioeconomic position (OR=2.2; 95% CI=1.2-4.2), traditional cigarette use (OR associated with smoking in 2011 and 2015= 13.1; 95% CI=5.2-32.6) and positive perceptions of e-cigarettes (OR =4.4; 95% CI=2.4-8.1) as well as asthma (OR=2.1; 95% CI=0.9-4.9) and overweight/obesity (OR=2.5, 95% CI=0.9-6.9). Factors associated with current use were traditional cigarette smoking (OR associated with smoking in 2011 and 2015 = 3.9; 95% CI= 1.3-12.2) and positive perceptions of e-cigarettes (OR =4.4; 95% CI=2.3-8.4). Conclusions Young adults who use e-cigarettes tend to persist in smoking traditional cigarettes. The conditions under which e-cigarette use can help individuals quit traditional tobacco products remain to be elucidated.