Abstract: In order to study the law of bulging movement of the blasting crater, the momentum conservation law was used to theoretically analyze the bulging movement speed, and experimental research was carried out by blasting funnel model test, high speed photography system and numerical analysis. The results show that the bulging movement rock mass was divided into numberless units, and the momentum conservation theory was used to obtain the blasting blaster bulging speed obeying exponential model. Through high-speed photography, the blasting drum bulging movement was recorded and analyzed. During the bulging movement, the free surface crack spread to the surrounding, so that the broken rock body presented a regular fan shape. With the uplift and rupture of the rock mass, the central point of the blasthole underwent variable acceleration. At different moments, the speed of movement decreased exponentially with the increase of the distance from the center of the blasthole. The speed of the bulge movement obeys the exponential model, and the center of the blasthole is the dominant variable acceleration motion, which decreases exponentially with the increase of the center distance of the blasthole. When the free surface bulge was completely broken, the broken rock mass was thrown at the maximum speed. When the angle of the projection was 45° with the horizontal, the farthest throw distance was reached.