Abstract: Based on the characteristics of hole-charged blasting,the mechanism of action, the stressing and the movement of the stemmingmaterial are analyzedaccording to the blasting theory and the stress wave theory, and theexpression of the lengthof the stemming material is deduced. On the basis of theoretical derivation andanalysis, the experiment of stemming and its effect on blasting results wascarried out. The experimental results show that the stemming in hole-charge isimportant and necessary. It may serve as a theoretical basis in the parameter design of blasting.