The riffle beetle genus Leptelmis is newly recorded in the Korean fauna with descriptions of two new species, L. coreana, n. sp. and L. ochra, n. sp. Dorsal habitus and line-drawings of diagnostic characters are provided. The adults of L. coreana and L. ochra are similar to those of L. gracilis Sharp or L. parallela Nomura in general appearance, but can be distinguished by the absence of apical spurs on the middle and hind tibiae, light brown body color, smaller body size, and the shape of aedeagus apex. Leptelmis coreana can be distinguished from L. ochra by the absence of hindwings, lack of prominent humeri and wider elytra in posterior portion. Adults of both species occur in lowland streams and large rivers, but L. ochra were encountered relatively infrequently.