Volunteer tourism as an alternative to mass tourism has grown significantly since the 1970s, sparking research interest in the subject. However, there is little research that has examined future potential volunteer tourists' various perceptions, needs and wants. The purpose of this study was to understand how and in what way various potential volunteer tourists' beliefs, including attitudes, subjective norms, self-efficacy and motivation, influence their future intended participation in a volunteer tourism experience using the revised theory of planned behavior. Moreover, the potential moderating effect of past volunteer tourism experience was examined as well. The study collected 291 usable responses from potential volunteer tourists who were active members of volunteer tourism organizations. The study used second order confirmatory factor analysis, structural equation modeling and hierarchical multiple regression analysis to test study hypotheses. The study also used meta-analysis to examine the effect size of the predicting variables and compared it with that of previous tourism research. The results of structural equation modeling indicated that two constructs, both attitudes and subjective norms, appeared to be statistically significant, while self-efficacy and motivation were not statistically significant in predicting potential volunteer tourists' intended participation. Hierarchical multiple regression analysis found a moderating effect of past volunteer tourism experience on motivation toward intended participation in a negative direction. In addition, the motivation factor "altruism" moderated in a negative direction. Meta-analysis found a large effect of attitudes, a medium effect of subjective norms, and a small effect of self-efficacy in relation to intended participation. In conclusion, the results did not validate the theory of planned behavior in the context of volunteer tourism research. Interestingly, the theory of reasoned action was found to be validated. Implications for volunteer tourism providers and organizations are also discussed.