Abstract: The stochastic optimization algorithm is studied and the model of the power management system is presented. IN the situation of system's response-delay, Markov decision method is applied to optimize the power management plan and the best power management strategy is educed. The analysis of the comparison demonstrates that despite efficient energy reduction in some dynamic power management there is considerable negative influence on the system's performance. The stochastic optimization algorithm can get favorable equilibrium between the energy consumption and the reliability of performance in the system.