On the basis of recoil in the process of blasting demolition of high buildings, this thesis applies dynamics theory to predict whether the phenomena of recoil wil occur or not by simulation and calculation of the recoil and the pressure suffered from the rudimental supporter in the process of demolition. The criterion of recoil relies on whether recoil can be overcome by the intensity of reservation or friction. To take the obliquity as increment,and to calculate the recoil and the pressure suffered from the rudimental supporter in correspondence with the every obliquity in the demolition by VC program, the relation curve can be obtained between recoil and obliquity.By means of examples testified with p r ograms,t he obtained results are consistent with those of p r actice.