Abstract: To research the influence of explosive specific charge change on bench blasting throwing results, a similarity criteria was deduced with dimension analysis method for the bench model test based on similarity theory. Five bench models with single-row hole were prepared in a test field using cement mortar in a certain proportion. Based on these bench models, the longest throwing distance and the effective throwout rate were got from explosion experiment. The results show that, anterior fragments of blast heap are mainly derived from the middle layer of bench model. With the increase of explosive specific charge, both throwing distance and throwout rate increase accordingly and gradually tended to be stable; when <i<q</i<<0.51 kg/m<sup<3</sup<, the cast percentage can reach more than 40%; as 0.51 kg/m<sup<3</sup< < <i<q</i< < 0.63 kg/m<sup<3</sup<, the cast percentage increases with explosive specific charge, and with a significant increasing rate; when <i<q</i<<0.63 kg/m<sup<3</sup<, the cast percentage increases with explosive specific charge, but with a smaller increasing rate.