Abstract: A reference wheel velocity calculation apparatus for use in an automotive vehicle includes a device for sampling actual wheel velocities detected at a predetermined sampling cycle, a device to select a suitable velocity as the basis of the calculation of reference wheel velocity, and a calculator for calculating an intermediate reference velocity of the present sampling point from the selected wheel velocity by suppressing the variance of intermediate reference velocity within predetermined limit(s). Further, a greater one of the presently sampled selected wheel velocity and a calculated intermediate reference velocity is selected as a quasi-reference wheel velocity which is then smoothed according to index to obtain the reference wheel velocity. The limit of the variance may be changed in regard to the accelerometer provided in the vehicle. Also, the smoothing index may be changed with respect to the factors such as the behavior of the wheel velocity.