Abstract: The empty-hole of parallel cut has an important influence on the cutting effect. Taking large-diameter empty-hole parallel cut and the small-diameter empty-hole parallel cut as the research objects, we analyzed the rock breaking mechanism of large-diameter empty-hole parallel cut through the theory and numerical simulation, and analyzed the blasting effect of empty-hole parallel cut with different diameters by combining with laboratory experiments. The research shows that the diameter of the empty-hole has an important influence on the blasting effect and blasting vibration of the parallel cut. The parameters such as the peak velocity and vibration duration of the small-diameter empty-hole are higher than those of the large-diameter hole. The blasting vibration velocity of large diameter empty hole is 20.6% lower than that of small diameter empty hole. The cutting depth of large-diameter parallel cut blasting is increased by 20%, and the damage range of tunneling working face is reduced by 30.8%. Combined with the analysis of cutting effect and blasting energy, the vibration consumption of blasting energy in the parallel cut with large diameter empty hole is smaller than that of the small-diameter empty-hole parallel cut due to the large free surface provided by the empty-hole. Most of the energy is used for the destruction of the rock in the cutting area, which reduces the damage of blasting vibration.