In a review of the genus Pyrausta (Lepidoptera: Crambidae: Pyraustinae) in the Korean peninsula, 12 species including three species of North Korea are recognized. Among them, P. nigrimaculata Bae et Kim is described as new to science, and P. chrysitis Butler is reported for the first time from Korea. A Key to species of the genus, based on the external characters, is provided. Morphological descriptions with illustrations of the genitalia for the all known species are given.