The characteristics of insect communities in specific localities reflect climatic and environmental status and change. We investigated the description pattern of new insect species by reviewing announcements of new or newly recorded insects in Korea published in five systematic journals between 1999 and 2009: Entomological Research (1999-2009), Insect Koreana (1999-2003), Journal of Asia-Pacific Entomology (1999-2009), Korean Journal of Applied Entomology (1999-2009), and Korean Journal of Systematic Zoology (1999-2009). A total of 757 new species were reported in 299 research papers. More than 85% of the newly described or reported species belonged to four orders: Coleoptera (225 species), Lepidoptera (202 species), Hymenoptera (141 species), and Diptera (82 species). The number of new species fluctuated from year to year, and a few major authors described most species. The graph of the cumulative number of species described in Korea was not asymptotic. We also examined the decadal trends in the proportion of species according to their biogeographical origin. The numbers of northern (Palearctic and Nearctic) and southern (Oriental) species recorded in Korea between 1999 and 2009 were increasing mainly due to the recent taxonomic research environment. It is also possible that recent climatic change induces new migrants toKorea from more southern parts of Oriental region, but more information is needed to confirm this hypothesis.