Carex taihokuensis Hayata (Cyperaceae) is reported from Jin-do (Isl.), SW Korea, for the first time. It belongs to sect. Digitatae, and had been known from Taiwan, China, and Japan. C. taihokuensis is characterized by the staminate terminal spike, bracts with sheath, pilose perigynia, and style base not thickened. We propose the new Korean name, ‘Jin-do-sa-cho’, after its first collecting place. We also provide a key to species in sect. Digitatae in Korea and Japan.