Abstract: 【 Purpose/significance】 To improve the open governance of medical data, a coordinating framework for medical data sharing is created in response to the current issues of a lack of fundamental principles, a lack of desire, and difficulty in safeguarding privacy and security hazards. 【Method/process】 This study takes the unpredictability of the external environment into account, constructs a stochastic evolutionary game model based on the strategy choice and the distribution of rights, responsibilities and benefits of medical data sharing involving hospitals, technology support enterprises and the government, and analyzes the strategy evolution of game sub⁃ jects through data simulation.【 Result/conclusion】 The study′s findings indicate that: technical support enterprises are key players in promoting medical data sharing, and their decision regarding a strategy is susceptible to initial probabilities, the proportion of construc⁃ tion costs to be borne, the proportion of privacy and security issues to be borne, the proportion of benefit sharing and stochastic pertur⁃ bations; the increase of additional cost effect caused by the hospital-government cooperation in construction will increase the enthusi⁃ asm of both parties to participate in cooperation; Hospitals′ choice of strategy will differ depending on whether technical support enter⁃ prises participate in medical data sharing construction of cost bearing; the benefits gap and the proportion of privacy and security is⁃ sues bearing will also influence hospitals′ strategy choice.【 Innovation/limitation】 The innovation of this paper lies in the combination of evolutionary game and stochastic process, which provides a new solution for the research of sharing and coordination mechanism among medical institutions, technology support enterprises and government in an uncertain environment, but other medical data sub⁃ jects and more comprehensive influencing factors are not considered, as well as the handling of multiple data is not yet found, which can be further explored subsequently.