In the alpine zone of Mt. Norikura, one hundred species in 13 families of the Lepidoptera were recorded during 17-19 August 2012. The investigations were carried out by the method of the route-census and collection by light trap. The females of Catoptria viridiana Bleszynski were recorded for the first time and many individuals were recognized at investigation site. The ratio of diurnal alpine species to the total number of collected specimens was 86.52 and to the total number of collected species was 22.22. The ratio of nocturnal alpine species to the total number of collected specimens was 27.42 and to the total number of collected species was 10.45.