This study investigated residents` perceptions on the marine tourism impacts on a town of Jeju(Kimnyeong) and its relationship with the residents` public support from the cost-benefit perspective. The social exchange theory was used to analyze the positive and negative aspects of DoBC(difference of benefit and cost). Data were collected from 198 residents of the town on September 2010. The main results of the study were as follows; First, the more the difference between benefits and costs were perceived, the better the respondents were likely to support of tourism development. Second, residents` positive attitudes for the benefits were positively related to their support for the marine tourism development, while their attitude for the costs were negatively associated with their support for the tourism development. Findings from this study suggest an integrated promotion of cost and benefits of marine tourism development impact for inducing residents` support for the tourism development.