Pear psyllids are of major economic concern in Korea. In the literature five nominal species, including two West Palaearctic taxa, are reported from the Peninsula. The Korean pear psyllids, member of the large genus Cacopsylla, are reviewed here to comprise four species. Previous Korean records of C. pyrisuga (Foerster) are misidentification of C. burckhardti Luo et al. whereas those of C. pyricola (Foerster) concern C. maculatili Li and probably C. jukyungi (Kwon) stat. rev., comb. nov. (from Psylla). The latter, that is commonly found in pear orchards, occurs also in Japan where it was misidentified as C. chinensis. The differences between C. jukyungi and C. cinereosignata syn. nov. reflect seasonal dimorphism. For this reason, we synonymise the two. C. maculatili and C. qiuzili Li are shown to represent the winter and the summer form of the same species and are, therefore, synonymised as C. maculatili = C. qiuzili syn. nov. C. jukyungi and C. sandolbaea (Park & Lee) are redescribed, a key to the adult of the four species and short biological notes are provided.

• Geonho Cho(Laboratory of Insect Biosystematics, Department of Agricultural Biotechnology, Seoul National University)
• Hiromitsu Inoue(Citrus Research Division, NARO Institute of Fruit Tree Science, National Agriculture and Food Research Organization)
• Daniel Burckhardt(Naturhistoriches Museum, Augustinergasse 2, CH-4001 Basel, Switzerland)
• Seunghwan Lee(Laboratory of Insect Biosystematics, Department of Agricultural Biotechnology, Seoul National University, Research Institute of Agriculture and Life Science, Seoul National University)