The invention discloses a blasting blocking dust fall device. The blasting blocking dust fall device comprises a water cannon bag body and a water cannon bag special tool; and the water cannon bag body is provided with a water injection cavity, a water injection channel cavity, a water injection channel, a water injection channel closed bag layer, a first-section water cannon bag, a water bag partition cavity, a high-pressure water channel, a second-section water cannon bag, a water cannon bag end air bag and an air nozzle. According to the blasting blocking dust fall device, the water cannonbag body is filled with high-pressure water, the contact area between the outer wall of the water cannon bag body and the inner wall of a blast hole is increased, the outer wall of the water cannon bag body makes closer contact with the inner wall of the blast hole through high pressure in the water cannon bag body, and the beneficial effects of replacing clay stemming to block blast hole is achieved; due to the fact that the length of the water cannon bag body is increased, the water cannon bag body can be completely suitable for the length of the blast hole, the water volume is increased, the water curtain range after blasting is enlarged, and the beneficial effects capable of better absorbing harmful gas and dust in blast smoke after blasting is achieved; and due to the design of the sectional type water cannon bag body, sequential rupture is achieved at the moment of blasting, the impact force generated at the moment of blasting is buffered, and the blast hole can be blocked more tightly.