At present, the testing link of the substation relay protection device still keeps traditional way, where the personal experience and working status of the test personnel have a great influence on the testing results during the whole testing process. Through the study of the intelligent automatic generation technology of the test cases of the relay protection device, this paper puts forward a kind of automatic test system architecture based on standardized module interface, which adopts an open extensible structure design thought and can provide protection basic template library for the test of different kinds of relay protection device. Application case analysis show that the method can greatly improve the editing efficiency of test template, and at the same time overcome the problems such as low efficiency of field test, overdependence on manual operation, non-unified test data format, etc.