The invention discloses a wind turbine generator control system software testing method based on software and hardware loop. According to the technical scheme, an actual wind turbine generator model is loaded, a measured control system is selected, measured control system software and a software simulating system are loaded and operated, a variable pitch system and a converter system corresponding to a measured system are chosen, a communication mode, a communication protocol and a communication address are set, a testing environment is operated, a testing configuration file corresponding to the measured control system is loaded, interfaces and data for the testing environment to interact with the wind turbine generator model are set, a testing case and procedures which are set already in the testing environment are operated, logic tests of all parts are carried out separately, testing work conditions and testing procedures which are set already in the testing environment are operated and a whole machine test is carried out, testing data is automatically stored, a testing report is automatically formed according to a preset specification, then the report is submitted for review, and a fault data form and a fault report are stored. The invention further discloses a wind turbine generator control system software testing device. The wind turbine generator control system software testing method and device based on the software and hardware loop have the advantages of being high in reliability, and comprehensive and systematic in testing.