The deformation of a spherical Liquid droplet colliding with a flat surface is numerically simulated in the range of Weber numbers from 10 to 10(3) and Reynolds numbers from 10(2) to 10(4), The maximum spreading diameter and the time required for the droplet to reach the maximum are correlated with the dimensionless groups and the dynamic contact angle. From a comparison between the developed models and experiments where the values of the dynamic contact angles are known, the models predict well the experimental results with respect to the dynamic contact angle. The models predict the experimental results from several published reports within 13% over the wide ranges of 5 < We < 2720 and 20 < Re < 2900, The prediction error of the present model for the maximum spreading diameter is smaller than those of previous models.