A monitoring method of a manufacturing execution system (MES), a monitoring device, and a readable storage medium are provided. The monitoring method of the MES includes: reading log files of applications of an MES distributed on multiple servers and monitoring business operation information of the MES according to the log files. Based on this, this can make up for a gap in MES service monitoring and timely respond to abnormal production conditions. In addition, operators do not need to perform log query on each server.