Abstract: Great emphasis has been placed recently on the development, application and associated capacity construction of health care big data in China. A centralized data sharing mode is currently adopted in China for efficient use of health care big data, but the incentive and restrictive mechanism in the data utilization are still imperfect under this mode. In this study, through analyzing the concept and mode of medical data sharing in the United States and Japan and systematically evaluating the performance in the construction of three aspects (capacity, pressure and motivation) related to health big data sharing in China, we proposed the centralized health care big data sharing mode with the participation of third - party – institutions certified by governmental departments in medical data processing; we also discussed some issues relevant to the proposed data sharing mode, including the incentives and restriction for different participants, laws and regulations on ownership of the shared data, and comprehensive management system.