The formation and development of networked air defense systems are not only necessary for adapting to anti air attack operations and responding to air and space threats， but also for promoting and guiding information technology and new combat theories. It is an inevitable choice for adapting to intelligent and networked operations of the system. As the critical basis for evaluating the success or failure of air defense operations， it has become an urgent task to assess the operational capability of air defense systems in the new mode. The article summarizes the research achievements in the field， analyzes the current research status， elaborates on the main problems faced， proposes the trend of networked operation of air defense systems， and suggests that the evaluation of air defense system combat capability has changed from “simple sum” to “emerging sum，” from “single result” to “result cloud，” and from “indicator tree” to “indicator network，” providing a theoretical reference for the evaluation of the combat capability of complex air defense systems with significant networked features in the future.