In the active distribution network（ADN）with high penetration photovoltaic（PV）generation，overvoltage due to the reverse power flow is the main cause limiting the output of the PV inverter.In this paper，a novel overvoltage preventive control method is proposed，in which three phase models are used.Firstly，the necessity of active and reactive power coordinated optimization for voltage control is analyzed by sensitivity analysis.Then，an active and reactive power coordinated optimization based overvoltage preventive control model is developed，in which DG and reactive power compensation devices are incorporated.Finally，extensive simulation tests on a modified IEEE123-bus three-phase test system are conducted.The numerical results show the proposed method is efficient and robust.