Using the coupled sine-Gordon equations，we investigate the motion of Josephson vortex in high-Tc superconductors. It is found that the oscillation behavior in the average voltage and resistance of Josephson vortex flow appear with the increasing of magnetic field in a fixed bias current. The period of the oscillation corresponds to the field, which has the magnitude of adding one Josephson vortex quantum per one intrinsic Josephson junction.