Abstract: The paper addresses the layout design of an international commercial global communication satellite.In order to optimize the layout of the satellite module,a two-stage （rough stage and exact stage） collision calculation method and a matrix transformation based mass property calculation method are investigated.Both methods are implemented in Pro/Engineer.The experimental results show that the collision calculation method is effective,and the mass property calculation method can be applied to obtain the mass property of the irregular objects or the objects with non-uniform mass distribution.