A simulation method for a macromolecular material comprises: a first calculation process for computing a Rouse parameter of a coarse-grained model; a second calculation process for computing a Rouse parameter of the a all-atom model; and a convert process for converting a unit system employed in a molecular dynamics calculation made by the use of the coarse-grained model into a unit system employed in the macromolecular chain, based on the Rouse parameter of the coarse-grained model and the Rouse parameter of the all-atom model.