Amur silver grass, Miscanthus sacchariflorus is one of the promising biofuel crops. A damage of noctuid pest, Leucapamea askoldis was firstly observed from Amur silver grass in Hwasun silver grass plantation during the survey of insect pests of Amur silver grass in Iksan, Hwasun, and Sancheong plantation areas in Korea. The host of L. askoldis was not known yet in Korea. Thus, M. sacchariflorus was the first known host in Korea. The L. askoldis damage was observed as larval feeding on newly grown shoots of M. sacchariflorus close to soil surface from early April to early May in 2013. Investigated larval density was 1.6 ± 1.1 per m2 on April 4 and damage rate of shoots was 0.8% ± 0.4 per hundred plants on May 4, 2013. The larvae bore into shoots of M. sacchariflorus and then feed inside of plant. The damaged shoots are easily pulled out and distinguished by the boring hole on the shoots.