The invention discloses a system and a method for automatically testing relay protection devices of intelligent transformer substations. The system comprises a cloud server, a two-dimensional code recognition device and a control and processing device. Two-dimensional code labels are arranged on the to-be-tested relay protection devices; the cloud server comprises data storage modules, and parameter data and two-dimensional codes of the relay protection devices are stored in the data storage modules; the two-dimensional codes on the to-be-tested relay protection devices can be acquired and recognized by the two-dimensional code recognition device, and the control and processing device comprises control and processing modules and data acquisition modules. The method includes acquiring the parameter data of the to-be-tested relay protection devices from the data storage modules of the cloud server according to two-dimensional code recognition result data by the control and processing modules; then generating corresponding test item list data and testing items one by one; acquiring test procedure parameter data by the data acquisition modules, generating test reports according to thetest procedure parameter data by the control and processing modules and outputting the test reports. The parameter data, which are about to be acquired from the data storage modules of the cloud server, of the to-be-tested relay protection devices correspond to the two-dimensional codes. The system and the method have the advantages that the relay protection device test efficiency can be improvedby the aid of the system and the method, and the test accuracy can be improved.