Via the WOS platform, the paper collects all literatures in the field of medical informatics from 2006 to 2015 and makes the bibliographic coupling analysis with Sci². It maps the knowledge graph of this field, analyzes the graph and generalizes the main research hotspots. It points out that medical informatics has involved wider research fields for the recent decade, including computer, clinical medicine and statistics, and has gradually developed into an inter-discipline concerning multiple disciplines and fields.