Korean species of Achyrolimonia, Dicranoptycha and Helius crane flies (Diptera: Limoniidae) are taxonomically revised. Identification keys, redescriptions and illustrations of all species and both sexes, if they were found in Korea, are presented. Genus Achyrolimonia is new record for the Korean peninsula, genera Dicranoptycha and Helius are new records for South Korea, species Helius (Helius) obliteratus (Alexander, 1920) is new record for the Korean peninsula and new record for the continent. Illustrations of females of D. diacantha Alexander, 1938 and H. gracillimus Alexander, 1938 are provided and female of D. prolongata Alexander, 1938 is described and illustrated for the first time.