Two Korean Alloeotomus species, A. chinensis Reuter 1903 and A. simplus (Uhler 1896), have been often misidentified each other because of the insufficient information and the erroneous description by Linnavuori (1963) on A. chinensis. This study provides detailed taxonomic information on these two Alloeotomus species from South Korea. Redescriptons on the two species are given with the photos of male and female specimens, live male adults, and vesica and left paramere of male genitalia.