A new species of the cave-dwelling springtail Lethemurus coreanus Chang and Bae, sp. n. is described from Korea. Lethemurus coreanus can be distinguished from congeners by the spinelike setae on the tibiotarsus, numbers of dental spines, number of setae on the trochanteral organ, and body macrochaetae chaetotaxy. A key to the species of Lethemurus is provided.