By means of distributed computing technology， a parallel computing method based on the computer cluster for online relay setting check is studied and developed. Firstly， the computing cost and characteristics of relay setting check are analyzed. Then the feasible methods are compared and finally the parallel computing method by means of power network partitioning is selected. The computer cluster is composed of one coordinating computer and some calculating computers. The graphic partitioning algorithm based on the seed node is executed in the coordinating computer and then the power network is divided into several parts. The relay setting in each part of the power network is checked by one calculating computer with the results collected by the coordinating computer. This method has been proved correct and efficient in actual application.