In the previous ten years, rural tourism has been the primary choice for most tourists from urban areas. At the same time, rural tourism industry is regarded as an important catalyst for rural revitalization. Despite its rapid development, series of problems regarding product, service and rural environment come into being. These problems result from ″the lag in the modern management capability of individual operators″ in the process of the development of agriculture, countryside and farmers. Rural tourism in China is largely dependent on rural community, and thus is inseparable from community support. In this sense, rural tourism development should be not only rich in tourism resources, but also in culture and connotation of community. Previous researches regarding residents' supporting attitude towards tourism can be divided into macro and micro levels. Macro researches generally followed the ″economy-culture-environment″ perspective and are concerned with the impact of residents' perception on their attitude towards tourism development. In contrast, micro researches focused more on tourist satisfaction, community involvement, and place attachment, which may also impact residents' attitude. Overall, residents' perception of the impact from tourism is still the mainstream of studying the residents' supporting attitude towards tourism. Recent researches have started to pay attention to the role of knowledge transfer in the formation of community residents' attitudes towards tourism. Theoretically, knowledge transfer is carried out through the social network, which is closely related to the social capital of the subject and object of knowledge transfer. Therefore, by introducing social capital theory, this study tries to construct and test the relationship modal of social capital, knowledge transfer and residents' supporting attitude towards tourism. Three rural communities in northern Zhejiang Province were selected, and data was collected through in-depth interviews and questionnaires, and analyzed with Structural Equation Modeling with the assistance of AMOS 17.0 software package. It is found that:（1）interpersonal trust, reciprocal cooperation and shared vision positively affect knowledge transfer by overcoming the conflict between individual rationality and collective rationality; （2）Interpersonal trust and reciprocal cooperation help residents to change their role from an ″individual rational person″ to a ″social man″ and thereby positively affect their supporting attitude towards tourism;（3）knowledge transfer has a positive impact on residents' supporting attitude towards tourism by promoting the residents' tourism innovation ability and management ability and the benefits from tourism development. Based on the above findings, this paper suggests that the community establish cooperating groups and learning groups to increase residents' support for tourism, promote knowledge transfer, and further promote the sustainable development of residents and communities. Meanwhile, tourism departments should play the role of knowledge intermediaries in tourism development. The major contributions of this study include:（1）It changes the previous research paradigm regarding residents' perceptions on tourism impact as the main factor of residents' supporting attitude towards tourism, and introduces the concept and theory of knowledge transfer into the research of residents' attitude, which may provide a new perspective.（2）Previous studies mostly emphasized the role of an ″individual rational person″ in the development of community tourism, while ignoring its role as a ″social person″. By introducing social capital theory, this study treats community residents as ″social persons″ embedded in the network of community relationships, and thus may more comprehensively explain the degree of residents' participation in and support of for tourism.（3）The applications of knowledge transfer theory in tourism research are mostly focused on hotels and tourist attractions. By focusing on the rural community of individuals or families, small businesses or social organizations, this study expands the application of knowledge transfer theory in tourism research.