The planthopper subfamily Achilinae (Metcalf, 1938) from Korea is taxonomically revised. Six genera and seven species are recorded among Korean fauna. Among them, one genus, Phenelia Kirkaldy, and two species, Phenelia striatella (Matsumura, 1914) and Deferunda qiana Chen and He (2010) are new to Korea. The male genital structures of all these species are described and illustrated, plus an identification key to the tribe, genus, and species is provided.