The current scenario of the Brazilian market is composed mainly of micro and small enterprises that grow every year, but have low survival rate compared to other countries. Once these businesses contribute greatly to the country s GDP, ensuring the survival of this group is of paramount importance to the Brazilian economy. In this work, a mathematical model was developed to optimize the production of a micro producer of snacks. Through the model, the quantities of inputs to be purchased from suppliers and the quantities of intermediate and final items to be produced in each period of the planning horizon are determined, in order to meet demand at a lower total costs. For this, a survey was conducted on the characteristics of the production of the studied micro company and it was observed that one of the reasons that prevent them from being competitive is the lack of knowledge and application of tools for planning and control of production. To evaluate the performance of the developed model tests were carried out with real data, and the results of different scenarios for the demand show that the model can be useful to support decisions on lot sizing of purchasing and production, showing that the obtained optimal costs are less than the costs obtained by the company without the use of optimization.