Propose/Significance A framework for medical data openness is constructed based on the information ecology theory to provide a systematic theoretical basis for the medical data opening in China. Method/Process By using the network survey method, 14 open medical data platforms are taken as the research objects, and the openness degree is compared and analyzed from multiple dimensions to build a framework for medical data openness. Result/Conclusion The information of the research objects is obtained and analyzed from 4 aspects:infrastructure, data governance, ethical norms and policy support, the indicators of medical data openness in the dimensions of information technology, information, information person and information environment are summarized, a framework for medical data openness is construsted.