This paper proposes a method for the coordinated control of reactive power of power distribution networks by means of multi-agent approach. The proposed multi-agent system consists of two types of agent: single feeder agent （F_ AG），and several bus agents （B_AGs）. In the proposed system，the F_AG plays as an important role，which decides the power factors of all distributed generators by executing the load flow calculations repeatedly. The voltage control strategies are implemented as the class definition of Java into the system. In order to verify the performance of the proposed method，it has been applied to the model system. The simulation results showed that the system is able to control very violent fluctuation the demands and the photovoltaic generations （PVs）.