The efficiency coefficient method is introduced to compensate the defects of the comprehensive weighted average method for multi-objective programming of power system. The principle of choosing the total power system cost, power loss, voltage offset, static voltage stability margin as the evaluation index based on the improved AHP to determine the weight of the corresponding evaluation index, the establishment of a comprehensive optimization model of power system. To IEEE 14 bus as an example, using the improved particle swarm algorithm was used to test the comprehensive optimization model, the results show that the comprehensive optimization model of power system with efficiency coefficient method has higher reliability and practicability.