An apparatus and method acquires acceleration data in a time series of a predetermined site of the tire during traveling of the vehicle, and removes an acceleration component due to a deformation of the tire from the acquired acceleration data to obtain a modified acceleration data, and performs frequency analysis of the modified acceleration data to obtain a frequency spectrum, and obtains an accumulated value of the frequency spectrum, and calculating a braking distance parameter for predicting a braking distance based on the obtained accumulated value, and obtains a predicted value of the braking distance of the vehicle based on the braking distance parameter calculated in the calculating part.