The current economic situation of the country brings to light the great responsibility of public managers in the administration of budgetary resources placed at their disposal. In times of contingency, when the Federal Government, in compliance with the Fiscal Responsibility Law, is obliged to determine that the Public Agencies reduce expenses, due to insufficient revenues, it becomes essential the efficient preparation of a plan aimed at the effective application of these resources in order to meet the desires of society. In this sense, the Armed Forces, aiming at carrying out the activities necessary to maintain national sovereignty, have been seeking tools to help them in the decision-making process and in the correct use of the amounts received. Thus, this dissertation aims to propose a model for optimal allocation of financial resources, in order to maximize the level of service, that is, increase the availability of the item in stock, under budget constraint. The proposed methodology was applied in a real case of the Brazilian Navy, in particular, in the Uniforms Division of the Navy Inventory Control Center. The results show that it is possible to significantly increase customer satisfaction with the available resources, since the model s solution raised the service level by 200 per cent, from the current 24 per cente to 74 per cent. In addition, the complementary modeling showed that an average increase of 8 per cent in the budget can generate continuous improvements in the service level, as well as a saving of 28 million real in the total amount needed to meet 100 per cent of the demand for all items, by comparing its solution with the result obtained from the system currently used, which makes it a useful planning tool.