A real coded genetic algorithm based PID controller (RCGAPID) is presented in this paper to improve power system dynamic stability. The proposed RCGAPID parameters are optimized using real coded genetic algorithm (RCGA). The design problem of the proposed controller is formulated as an optimization problem and RCGA is employed to search for optimal PID controller parameters. Integral absolute error (IAE) and integral squared error (ISE) performance indexes have been used for the determination of the PID controller parameters in power systems stabilization. The performance of the proposed RCGAPID under various loading and small disturbance conditions are analyzed and compared in single machine infinite bus (SMIB) power system. Simulation results show the effectiveness and robustness of proposed controllers to improve the stability performance of power system. Copyright (C) 2010 Praise Worthy Prize S.r.l. - All rights reserved.