Abstract: Based on the contact force characteristics in the interface between the free-standing equipment and base, a sliding-kicking up model for free-standing equipment under explosion seism impact is proposed by Matlab/SIMULINK software, and its correctness is verified. The dynamics equations and the critical conditions of different motion states are solved out. The motion process of the free-standing equipment in the real explosion environemnt can be divided into four stages including conglutination, sliding, free flight, hard stops by inputting the real explosion acceleration wave to this model. A reasonable simplified acceleration is developed, and by which variation of the motion response of the free-standing equipment with the kinetic friction coefficient and explosion seism parameters is obtained.