The males of four new species of Cybaeus L. Koch, 1868 (Cybaeus yeongwolensis sp. nov., Cybaeus culter sp. nov., Cybaeus vanimaculatus sp. nov., and Cybaeus pseudoauriculatus sp. nov.) are described from leaf litter habitats in South Korea. We provide diagnoses, detailed descriptions, a key to the males of Korean Cybaeus species, and a distribution map for these new species. They appear to be endemic to South Korea and were collected from mixed forests in hilly and mountainous terrain.