The genus Synanthedon Hübner, 1819 belong to family Sesiidae described about 51 species in the Palearctic region (Špatenka et al., 1999). Genus Synanthedon characterized by following characters (Špatenka et al., 1999): Antenna occasionally with a white apical spot; labial palpus smooth or weakly tufted; transparent areas of forewing (ATA, PTA, ETA) usually present; hindwing transparent; abdomen with large anal tuft in male. Matsumura (1931a, b) reported two species of the genus for the first time from Korea, they are mainly studied by Inoue et al. (1982), Park et al. (1983), Park (1986), and Arita et al. (2004). Presently, genus Synantedon have included the following eight species in Korea (Arita et al., 2004): S. bicingluata (Staudinger, 1887), S. ulmicola Yang & Wang, 1989, S. haitangvora Yang, 1977, S. unocingulata Bartel, 1912, S. velox (Fixsen, 1887), S. tenuis (Butler, 1878), S. martjanovi Sheljuzhko, 1919, and S. quercus (Matsumura, 1911).
In this study, four new species belonging to the genus are described based on morphological characters.

• Cheol-min Lee(Entomological Laboratory, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Japan)
• Yang-seop Bae(Department of Biology, College of Natural Science, University of Incheon)
• Arita Yataka(Zoological Laboratory, Faculty of Agriculture, Meijo University, Japan)