For an industry, production capacity is defined as the maximum level of output that plants can maintain within the framework of a realistic work schedule, taking account of normal downtime, and assuming sufficient availability of inputs to operate machinery and equipment in place. Such capacity is one of the important and basic due to measure, manage and evaluate the production performance and ability of any industrial bodies. However, the estimating methods now in use in Korea are seemed far from the definition above. And there are not any standard estimating method suggested even in the same sort of manufacturing and also no applicable theory for objective and exact measurement. Thus, in this paper, a new measuring model is suggested as standard and supporting theories are developed for general measurement purpose to any manufacturing industries.