Korean oak wilt (KOW) caused by Raffaelea quercus-mongolicae and its vector, Platypus koryoensis is one of the most severe forest pests in Korea. In spite of its importance, information about dispersal of P. koryeonsis is very limited. In here, a hypothesis related to long distance dispersal (LDD) of KOW reflecting behavior of P. koryoensis is proposed. When attack density of P. koryoensis increased, location of entry holes in the trunk moved to upward. The individuals which escaped from entry holes in upper trunk had potential to fly upper part of trees and they flew longer distance probably by aid of winds. We suggested that this density dependent dispersal of the beetle explain the spatial dynamics of KOW in large scale.