This paper takes the tourism in the city of Xiamen as the research sample, adopting system analysis method, concentrating on the impacts of climate change on tourism's development, building the relevant index system, and adopting analytic hierarchy process to calculate the weight of each index. Besides, it also applies fuzzy comprehensive evaluation to evaluate each index, performing the quantitative analysis of the impacts of climate change on tourism in the city of Xiamen. According to the research, the maximum membership grade of the impacts of climate change on tourism is 0.309, which is relatively high. According to influential degree, this research can clearly classify various parts which are affected by climate change in the process of tourism's development. Therefore, it can effectively instruct tourism practitioners to implement risk classification, have a clearer understanding of the impacts, further coordinate the interests of different parties, achieve pertinent promotion and realize the long-lasting utilization of tourism resource and the sustainable development of tourism.