Establishing national park system is an import strategy adopted by the Chinese government to better conserve the integrity and primitiveness of its large natural ecosystem, and to achieve the goal of ecological civilization and the modernization featured with the harmony between human being and nature. Local resident is not only one of the most important stakeholders in the process of establishing and managing a national park, but also is an active and significant force in conserving the natural ecosystem of a national park. In this sense, how to foster and strengthen the positive attitude of local residents toward nature conservation is of high importance for establishing and managing a national park. By introducing place attachment as intermediary variable and taking Shennongjia Pilot National Park as a case, the authors propose in this paper a structural relation model which conceptualizes tourism impact perception and place attachment and nature conservation attitude, and then employ multi-group nested Structure Equation Modelling (SEM) to reveal the mechanism that how national park tourism influences local residents' attitude toward nature conservation. The results indicate that: (1) the local residents' perception of tourism impacts has significantly direct impact on their attitude toward nature conservation; (2) The place attachment of local residents plays a significant intermediary role between the perception of tourism impact and their nature conservation attitude; (3) In terms of the structural relations among local residents' tourism impact perception, place attachment, and nature conservation attitude, there exists a significant group difference between the residents participating in tourism and those not. For the residents participating in tourism, their perception of negative tourism impact exerts no significant impact on both place attachment and nature conservation attitude. For the residents not participating in tourism, their perception of negative tourism impact can significantly and adversely influence their attitude toward nature conservation, which works directly or indirectly through place attachment. This study has two theoretical contributions to the study of nature conservation attitude of local residents living within the protected areas. One is to have revealed the mechanism of how national park tourism influences the attitude of local residents toward nature conservation through the intermediary role of place attachment. The other one is to have further unveiled the group difference in the impacts of national park tourism on local residents' nature conservation attitude through the comparative analysis of the two groups of local people (i.e. those participating in tourism and those not).