Abstract: In order to study the phenomenon of deposited coal dust explosion induced by gas explosion, the experiments were carried out in the experimental road way with single head, and the ability of induction to deposited coal dust and propagation law were researched by different intense of impact flow in gas explosion with di fferent volume. The results showed that the impact flow of gas explosion could hoist deposited coal dust to participate propagation, form dust explosion, and expand the scope of damage. When the volume of gas area increased from 50 m3 to 200 m3, the peak pressure of impact flow increased from0.14 MPa to0.31 MPa, and the induci ng capacity of deposited coal dust was enhanced. The maximum pressure in test section was 0.36 MPa and 0. 83 MPa, and the no- coal dust flame length was 75. 1 m and 115. 2 m respectively. The explosion process would be more rapid.