The penetration ratio of distributed generation (DG) has increased due to the depletion of fossil fuels and the impacts of global warming. Thus, overvoltage at the point of common coupling may occur since reverse current flows with the installment of DG. To solve this problem, this paper presents a reactive power control method based on the measured current at the point of common coupling of DG. The purpose of this paper is not to provide methods to improve the voltage profiles of distribution lines through the reactive power control, but to maintain the voltage after the DG connection as before the connection. By applying the proposed method in this paper, it is possible to significantly improve the penetration ratio of DG by restricting the voltage rise. Case studies, using MATLAB simulation, are performed to verify the feasibility of the new reactive power control method.