Abstract: Based on the results of a small scale experimental models and the observed data in the productiveblasting at Baiyun'ebo Iron Mine, some new viewpoitS about blocky rock mass movement in benchblasting are presented, also reasonable millisecond delays between blasthole rows and the quantity rela-tions of the beginning velocity of rock mass moving with blasting paramaters are gived. It provides thethorey basis for mine's controlling rational blastpile parameters.