Climate change adaptation capacity remains low among vulnerable communities in developing countries such as Vietnam. Vector-borne diseases as dengue fever are increasing as a result of changing weather patterns. This study aims to examine the impact of key psychological variables in the Theory of Reasoned Action, the Theory of Planned Behavior, an Extended Parallel Process Model and the Social Cognitive Theory on the intention of schoolchildren to engage in climate change adaptation behavior—in this study, practices which would help reduce the risks of contracting dengue fever. It also seeks to identify the most salient predictors of the behavioral intention across these theories. Data were obtained from 796 Vietnamese schoolchildren who completed questionnaires measuring constructs of the four theories. Multivariate data analysis demonstrated that self-efficacy and severity appeared to be significant and consistent predictors of the individual’s intention to reduce dengue fever. The results provide practical suggestions for the use of the theoretical constructs tested in climate change communication campaigns in Vietnam and insights generally on pro-environmental behavior change.