The purpose of this study is to develop a scale for measuring the tourists’ connection to nature in the context of Chinese national wetland park. Following a rigorous process of scale development, a three-dimension (natural identity, emotional affinity, and natural dependence) model of connection to nature is established. The study develops 12 measurement items to construct a survey instrument of tourists’ connection to nature. To test the predictive validity of the scale, pro-environmental behavior is measured as an outcome variable of tourists’ connection to nature. The study tries to provide a framework for future empirical investigations in nature-based tourism settings, and offer a useful tool for such purpose.