In order to change the mode of intelligent substation relay protection maintenance, the monitoring information is selected according to the relay protection device fault condition and a collection and analysis method of relay protection monitoring information is proposed. By introducing the theory of fuzzy mathematics, the relay protection state evaluation model is set up based on the fuzzy comprehensive evaluation thoughts and the state information is represented by the membership function. The quantitative assessment is carried out with online monitoring and record information of relay protection device and the running state of the relay protection is defined. An example shows that this evaluation method is reasonable and effective. The application of condition assessment has converted past regular maintenance into condition-based maintenance, which can reduce the maintenance costs of relay protection effectively and improve the reliability of substation system.