Purpose/Significance To clarify the construction mode and key factors of data sharing in Chinese medical alliances, and to provide references for promoting data sharing in medical alliances.Method/Process Taking children’s medical alliance of Yangtze River Delta as an example, Delphi method and qualitative interview method are used to explore the key contents and effect evaluation of specialty alliance construction, and the key factors of specialty alliance data sharing are defined based on the technology-organization-environment framework; SWOT analysis model is used to propose development strategies. Result/Conclusion Member hospitals are less satisfied with the construction effect of information interconnection. Key factors for realizing data sharing in specialty alliances include:support from government administrative departments, uniform and systematic compatibility of information standards, information security emergency response, patient privacy protection and informed consent, willingness of department directors to share, and internal communication and compensation mechanism of alliances.