To coordinately consider the economy and security of the system during reactive voltage control， a multi-objective reactive power optimization model is proposed. Apart from the conventional economic objective， the new model has the system static security added to the multi-objective to seek their optimization simultaneously. And the solution for the model is proposed based on the cooperative game theory. As two players of the game， the economy side and the security side decide on their game strategies alternately until equilibrium is attained. Tests on a 2-bus system and IEEE 9-bus system demonstrate the feasibility and advantages of the model along with the proposed method.