In order to deal with the semantic non-standard phenomena in the field of relay protection currently, this paper designs a kind of relay protection information semantic intelligent recognition algorithm based on four modules including dictionary management, semantic matching, retrieval pre-processing, and retrieval management. Combined acquisition and storage algorithm, pre-processing algorithm, and text similarity algorithm, an intelligent self-learning based semantic intelligent processing mechanism is designed, which realizes the semantic statistics of non-standard relay protection through gradually improving computer self-recognition rate, thereby enriching semantic knowledge accumulation and then increasing the accuracy of non-standard semantic standardization. According to the testing of different types of non-standard semantic data, the obtained standard semantic datum are analyzed and verified, which proves that the relay protection information semantic intelligent recognition algorithm has good performance and feasibility.