Since some shortconmings as timeconsuming, poor accuracy and difficult expansion, traditional manual testing method has bottlenecked the rapid development of radar testing technology,so we have to build new ones urgently. Based on standard system bus and specially designed adapter, the generalpurpose automatic test system can test diversified modules or plugins of many subsystems. After recognise the adapter ID, automatic test system execute corresponding testing schema automatically. Testing management system can analyse and diagnose the fault of equipment under test (EUT), trace back to fault causes from fault phenomena. Then, it put forward fault diagnoses method, finally implement fault localization. Through practical application, it has been proved that the system has good versatility, high degree of automation, really implement the instruments parameters automatically set, automatic data acquistion, automatic storage of the test results and many other functions. Furthermore, the radar generalpurpose automatic test system show the construction of perfect function, stable performance.The system played an important role on R&D process and Maintenance of an exported radar.