The present invention provides a printed wiring board design aiding apparatus, method, and program that can easily and inexpensively predict the displacement of a printed wiring board of complicated shape and configuration due to temperature change. The printed wiring board design aiding program makes a computer execute the steps including a mesh division step that divides an analytical model of a printed wiring board obtained as data into meshes, a mesh displacement calculation step that calculates displacements of respective meshes of a printed wiring board which is divided in the mesh division step, a mesh displacement connection step that connects mesh displacements calculated in the mesh displacement calculation step so that the inclination of borders of respective meshes become equal, and a displacement calculation step that calculates a displacement using an entire displacement of a printed wiring board which is obtained in the mesh displacement connection step.