On February 24, 2008, a twin low pressure system caused very high wave condition on the whole coast of the Japan Sea. The Yorimawari-Nami, peculiar long period swells to the sea, entered Toyama Bay and gave unexpected damages in the coastal and port areas. This paper, therefore, describes the significant waves and spectrum profiles of the swells observed by the coastal wave observation network NOWPHAS. The significant wave height and period on thewave record reached 9.92m and 16.2s at Toyama Station on a submarine peninsula in the bay. The shallow water wave simulation with the Boussinesq model led the wave energy focusing in some areas due to the peculiar bathymetry with submarine peninsulas and steep slopes in the bay, called Aigame in the district.