The invention discloses a distributed log analysis based operation state monitoring method of a power system. The method comprises the steps of S1, acquiring log information of the power system, and combining into a log file; S2, segmenting the log file, processing to obtain the log information with the same format, respectively sequentially outputting the log information in the log file into a distributed storing system; S3, extracting the log information from the distributed storing system, classifying the log information by the log analysis algorithm based on state noise removing and clustering according to the Map-Reduce mechanism, and analyzing the classified log information to monitor the system operation state. With the adoption of the method, the abnormality in operation state of the power system can be timely found if any and can be handled at the first time, so that the requirement on timely and efficient operation of the power system can be effectively met.