Background: Calls have been made to relax current Australian regulations related to e-cigarettes to increase the accessibility of the devices for smoking cessation purposes. However, e-cigarettes have been found to increase risk of initiation of conventional cigarette smoking, especially among young adults. To assist in guiding the development of policy in Australia, the present study examined whether e-cigarette use among Australian young adults who have never smoked a tobacco cigarette is associated with susceptibility to future tobacco cigarette use. Method: An online web panel provider recruited 519 never smokers aged 18–25 years (55% female; average age = 21.21 years, SD = 2.32). Respondents completed an online survey that assessed their curiosity about tobacco smoking, willingness and intentions to smoke, and a number of individual and social factors. Cross-sectional regression analyses were conducted to assess the association between e-cigarette use and susceptibility to tobacco cigarette use while controlling for multiple covariates. Results: Curiosity about tobacco smoking, willingness to smoke, and intentions to smoke were significantly higher among users of e-cigarettes than never users. The relationship between e-cigarette use and susceptibility to future tobacco cigarette use remained significant after controlling for numerous covariates. Conclusion: E-cigarette use, even just one or two puffs, has the potential to increase susceptibility to tobacco cigarette use among Australian young adults. Findings suggest that increasing the availability of e-cigarettes by relaxing current strict regulations surrounding their sale may have unintended consequences.