Abstract: To investigate the characteristics of bulging motion of model free face in blasting crater experiment, this paper performed the blasting crater experiment by building a similar material model of Heidaigou open cast coal rock based on similarity criterion, and measured the depth, radius, volume of blasting crater.Furthermore, this paper built a full-scale calculation model for blasting funnel experiment based on AUTODYN, and compared the numerical simulation results with the experimental measured data, and found that the crater radius and depth of both data are similar.Through extricating and analyzing the displacement, speed and acceleration time course of Gaussian point set in the model, it can conclude that the bulging motion of rock blast is subjected to an integrated effect of blast shock wave, blasting gas, collisions between rocks, and gravity.Moreover, the bulging motion successively goes through acceleration, deceleration, constant speed, second acceleration and second deceleration.