The purpose of this study examined the factors that influence local community residents’ support for the Upo wetland as a Natural Reserve and their support for sustainable tourism development. Community attachment, environmental attitudes and involvement in Upo wetland were hypothesized as independent variables. A factor analysis was used to delineate underlying dimensions of tourism development impacts and a regression analysis was used to investigate relationship. Results of a regression analysis using 163 resident samples suggested that community attachment and environmental attitudes positively influence their support of sustainable tourism development, and in particular environmental attitudes indirectly influence the support behaviors through residents’ perceptions(the feeling of wetland conservation) about Upo wetland. Level of Involvement in the Upo wetland was not found to have any significant relationships. The notable lack of involvement of residents presented critical implications for the sustainability of the site.