26 species of Korean Scarabaeidae, containing one new species scientific, were identified from 6,702 specimens, of which 5,159 were collected in south Korea after the year 1981 and 1,543 of southern and northern samples stored in the museum of several universities. Also, of 157 reports on the Korean fauna of this family were examined, and they recorded 82 names from the Korean Peninsula. But we can recognize 31 species of those, and 51 names was the errors by the synonyms, the misidentifications, the misprints and the other mistakes. Therefore, The Korean Scarabaeidae was 32 species containing one new species belonging to 7 genera of 2 subfamilies. And this report is a synopsis for 21 species on the genus Onthophagus, succesive series of reports from other groups(11 sp. of 6 gen.) of 1st and 2nd report(Kor. J. Ent., 14(1):51-61 and 14(2) :19-22). The new species O. koryoensis is described on the page corresponding and the 3 names O. koma, nakatomii and shozozanus are junior synonyms.