An active vibration noise control apparatus with which vibration noise can be reduced stably and effectively by preventing divergence of a filter coefficient or a delay in convergence due to an effect of a transfer characteristic on a secondary path. The active vibration noise control apparatus calculates an update step size in accordance with a magnitude of a gain in the transfer characteristic corresponding to a frequency of vibration noise, where the transfer characteristic is on the secondary path for propagation of a secondary vibration noise for reducing the vibration noise, and updates the filter coefficient on the basis of the calculated update step size.