The tribe Bythinini Raffray is species-rich pselaphine group including over 600 species distributed worldwide. Despite its diversity, only one genus, Bryaxis Kugelann, has been reported in Korea. In this study, we newly describe Bryaxis sp. n. mainly based on the male antennal modification. We also report a new species of the genus Tychobythinus Ganglbauer from Korea. Members of these two bythinine genera are commonly characterized by the traits of maxillary palpi: elongated second palpomere, shortened penultimate, and enlarged last one. In addition, we conducted phylogenetic analyses to demonstrate the relevance between antennal modification and evolutionary relationship of Bryaxis. To perform the phylogenetic construction, we assembled three mitochondrial genes (cox1, cox2, and 16S) and three nuclear genes (18S, 28S, and wingless) into a dataset. Eleven species of Bryaxis and two Tychobythinus species are included, the latter genus of which are used to root the consensus trees.