The blueberry gall midge, Dasineura oxycoccana (Johnson), was recently invaded into Korea, which causes serious damage to blueberries. In the blueberry production regions, the gall midge affects most blueberry varieties, Vaccinium spp., such as rabbiteye and highbush blueberries, causing substantial yield loss by damaging flower and leaf buds. Last year we investigated and collected the midges in the blueberry farms from Korea and USA (New Jersey and Georgia). To confirm inter- and intra-specifc variations of D. oxycoccana, we tested COI DNA barcode using 180 collective individuals plus 37 GenBank references including other Dasineura species. As results, we found the same haplotype from 126 individuals in Korea, USA, and Canada. Most of the remaining haplotypes were closely related to the former, whereas there were 7 unique haplotypes genetically very distant from the major haplotype. Especially, the two haplotypes in Cheonan, Korea, were genetically farthest from the major, and the existence of two different species in New Jersey and Sunchang were confirmed. We would present haplotype diversity and geographic relationships of D. oxycoccana.