A study on the plant parasitic nematodes (Tylenchida) in JeJu province has been undertaken to know the kinds and distribution of the nemic fauna. The 42 samples taken from 28 kinds of host plants were used. 1. The 22 species belonging to 16 genera in 10 families were discovered in this study and among them Meloidogyne was the most common and widely distributed genus, composing 25%, followed by Helicotylenchus 1596, Criconemoides 1496, Tylenchus 10%, Pratylenchus 6%, Neolobocriconema 6%, Aphelenchus 6%, Aphelenchoides 6%, Hirshmaniella 396, Heterodera 3% Nothotylenchus 1%, Tylenchorhynchus 1%, Merlinius 1%, Rotylenchus 1% Discocriconemella 1% and Hemicriconemoides 1%. 2. The 11 species belonging to 10 genera in 7 families such as Nothotylenchus acris, Tylenchorhynchus dubius, Merlinius nothus Pratylenchus minyus, Pratylenchus thornei, Hirshmaniella imamuri, Rotylenchus robustus, Helicotylenchus erythrinae, Meloidogyne arenaria, Discocriconemella hengsungica and Aphelenchoides besseyi were newly discovered species in JeJu province.