A method to reduce the drift of reflective fiber-optic current sensor (RFOCS) is proposed. By employing Y-waveguide to instead the coupler-polarizer part in the RFOCS system, the extinction ratio of the system is enhanced. The experiment results show that the drift of the RFOCS is reduced from 11.1A to 1.58A after employing Y-waveguide, which provides the theoretical and experimental basis for the practical application of RFOCS.