The fluid-solid coupling algorithm is applied in the numerical simulation of explosive compaction of porous copper. A three-dimensional model is build that consists three parts: air, explosive and pore copper. The results show that the pressure on side wall increases with the propagation downward of detonation waves. The increase of angle between sliding detonation front and side wall of pore copper causes the increase of pressure. When the angle reaching 90 degree, stable detonation is formed and the pressure reaches maximum about 85% of detonation pressure. The fluid-solid coupling algorithm that can avoid meth distortion is very suitable for calculating large deformation problem in explosion mechanics region.