This paper presents an availability optimization problem of an engineering series system, which has the redundancy of subsystems and the number of teams of maintenance as optimization parameters. The objective is to reach the maximum value of the availability, considering installation and maintenance cost, weight, volume and available maintenance teams as restrictions. The optimization method used was the Genetic Algorithm, which is based on biological concepts of species evolution. It is a robust method, because it does not converge to local optimum. It does not need the use of differential calculus, facilitating the computational implementation. The proposed search method (Genetic Algorithms) is easy to be implemented and suficinetly robust for the proposed problem. It reached the global optimum region with this method.1324754Doty, L.A., (1989) Reliability for the Technologies, , New York: ASQC Quality Press BookRamakumar, R., (1993) Engineering Reliability: Fundamentals and Applications, , Oklahoma: Prentice-Hall InternationalWohl, J.G., System operational readiness and equipment dependability (1966) IEEE Trans. Reliability, R-15 (1), pp. 1-6Lewis, E.E., (1987) Introduction to Reliability Engineering, , John & Wiley & Sons, IncHolland, J.H., (1975) Adaptation in Natural Artificial Systems, , University of Michigan PressHsieh, Y., Chen, T., Bricker, Genetic Algorithms for reliability design problems (1998) Microelectronics and Reliability, 38 (10), pp. 1599-1605Painton, L., Campbell, J., Genetic algorithm in optimization of system reliability (1995) IEEE Transactions on Reliability, 44 (1), pp. 63-72. , MarchGoldberg, D.E., (1989) Genetic Algorithm in Search Optimization and Machine Learning. Reading, , Mass.: Addison-WesleyMitchell, M., (1996) An Introduction to Genetic Algorithms, , Cambridge, MITMichalewicz, Z., (1996) Genetic Algorithm + Data Structure = Evolution Programs, , New York: SpringerCastro, H.F., (2003) Otimização da Confiabilidade e Disponibilidade em Sistemas Redundantes, , Universidade Estadual de Campinas - Dissertação de MestradoKumar, A., Pathak, R.M., Gupta, Y.P., Gemetic-algorithm-based reliability optimization for computer network expansion (1995) IEEE Transactions on Reliability, 44 (1), pp. 63-72. , MarchRubinstein, R.Y., Levitin, G., Lisnianski, A., Ben-Haim, H., Redundancy optimization of static series-parallel reliability models under uncertainty (1997) IEEE Transactions on Reliability, 46 (4), pp. 503-511. , DecemberLevitin, G., Redundancy optimization for multi-state system with fixed resource-requirements and unreliable sources (2001) IEEE Transactions on Reliability, 50 (1), pp. 52-59. , MarchHsieh, Y.C., Chen, T.C., Bricker, D.L., Genetic algorithms for reliability design problems (1998) Microeletronics Reliablity, 38 (10), pp. 1599-1605Coit, D.W., Smith, A.E., Reliability optimization of series-parallel system using a genetic alorithm (1996) IEEE Transactions on Reliability, 45 (2), pp. 254-266. , JuneYang, J., Hwang, M., Sung, T., Jin, Y., Application of genetic algorithm for reliability allocation in nuclear power plants (1999) Reliability' Engineering & System Safety, 65, pp. 229-238Taguchi, T., Yokota, T., Gen, M., Reliability optimal design problem with interval coefficients using hybrid genetic algorithms (1998) Computers and Industrial Engineering, 35 (1-2), pp. 373-376Castro, H.F., Cavalca, K.L., Reliability optimization of redundant system (2002) SAE Technical Papers, 1 (1), pp. 1-9. , Danvers MA USAErtas, A., (1993) The Engineering Design Process, p. 525. , John Wiley & Sons Inc