The purpose of this study is to investigate the mechanism related with academic engagement that can explain adult learners’ behavioral intention. For this purpose, we are going to analyze structural relationship among adult learners’ self-determination, academic engagement, satisfaction, and behavioral intention. We planning to survey adult learners who participate in the lifelong learning programs in lifelong learning institutions. And we are examining the content validity of a questionnaire to apply to adult learners. Based on this study, we’ll summarize what the empirical evidence is for the effect of academic engagement and suggest areas for future research.