Superconducting magnetic energy storage (SMES) system is an equipment that can help improving the stability of a power system. Location of SMES in multi-nodes power network plays a significant role for the stability improvement level. In this paper, based on the quantitative voltage stability index, genetic algorithm (GA) is used for optimization of the SMES location. The voltage stability index is used as the fitness function in GA. The GA mathematic parameters and optimal flow chart are presented. The proposed algorithm is tested in an IEEE 14-bus system. Simulation results show that the SMES is settled on the best site through GA optimization during the period of the voltage stability fault.