In order to procure a just evaluation of the damage and the effect of explosion phenomenon， it is necessary to evaluate the fragments created by the explosion. In this study, the fragmentation of steel and resin tubes by two ammonium nitrate - based explosives was examined. The fragnent velocity of the water - gel explosive and ANFO were measured, and the fragment velocity was influenced by the size of fragments. The Gurney equation was adapted, and the energy related to the fragmentation of the resin tube was different from that of the steel tube. The fragments of tubes by ANFO were collected and adapted to the Held type distribution model. The Held model was a good adaptation for the distribution of fragments of not only steel but also resin tubes．The value of the constant B was influenced by the tube materials.