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An economic production quantity (EPQ) model plays a momentous role in production and manufacturing units. In this paper, we introduce four stages of production inventory model for deteriorating items in which three (Beginning, Developing and Maturity) different stages of production and one decline stage are considered. The demand is assumed as exponentially increasing and production is demand dependent. In an inventory cycle, the production facility can produce items in a determined number of replenishment cycles under finite time horizon. The shortages are permitted and completely backlogged. The purpose of this research is to investigate the optimal production lot size and total cost during the product life cycle (PLC) which consists of beginning, developing, maturity and decline stages. Necessary and sufficient conditions for a unique and optimal solution are derived. Finally numerical example and sensitivity analysis on parameters are made to validate the results of the proposed inventory system.