Based on the explanatory structure model, using the literature analysis method and expert consultation method, we screened, supplemented and determined the influencing factors for the construction of integrated healthcare service system, sorted out the hierarchical succession relationship among the influencing factors, and analyzed the role mechanism among the factors at different levels in the explanatory structure model, so as to provide reference for the construction of integrated healthcare service system. The study shows that the influencing factors for the construction of integrated healthcare service system are divided into 7 levels, which can be summarized into 3 levels, namely, the appearance level, the intermediate level and the decision level, among which the professional service synergy and so on are the appearance level factors, the governmental financial support and so on are the intermediate level factors, and the regional economic condition and so on are the decision level factors. In order to enhance the ability to build an integrated healthcare service system, it is necessary to rationally allocate healthcare resources and enhance the capacity of primary healthcare services; to build a high-quality information service system that is deeply embedded in healthcare services; and to improve the synergy of interests and incentive mechanisms to create a close community of interests.