OEE(Overall Equipment Effectiveness, OEE)is a crucial method to measure manufacturing effectiveness. It is to detect and to solve the bottleneck problem of manufacturing lines. It is obvious that its measuring methods and frameworks have been applying in diverse relevant researches, yet the using methods as well as manipulating process has yet to elaborately mention. Therefore, this study is to present comprehensively step-by-step of OEE implementation process, and to formulate standard measuring methods, which is a helpful reference for the companies which are intending to apply OEE to formulate their own standard criteria of OEE. From the total productive maintenance of the case company, this study focuses on its small group maintenance in order to establish basic data, calculating frame, manipulating process, from which clearly clarifies the total steps of OEE as well as its effectiveness.