Abstract: A power supply noise analysis model generator models power supply layers in circuit boards, and includes: a CAD data obtaining section that obtains CAD data; a CAD data conversion section that converts CAD data into data suitable for noise analysis; a power supply pair extraction section that extracts a power supply pair; a mesh division section that divides a power supply pair region into meshes; a ripple processing section that arranges ripples as wave fronts of electromagnetic waves radiated into the power supply pair region from elements thereon; a node layout section that positions plural nodes on the power supply pair region; a node region determination section that determines node regions; an LRC determination section that determines L, R and C connecting the nodes; a power supply layer model generation section that generates a power supply layer model; and a power supply noise analysis model generation section that generates a power supply noise analysis model.