Here we report the first finding of Cryptonemia rotunda and Schizymenia apoda in Korea based on plastid rbcL sequence analysis and morphological observations. C. rotunda occurred in the subtidal in Hongdo and Namyeodo on the south coast. Thalli have short stipe with foliose, membranous blades with dentate margin, a length of 2-8 cm. S. apoda occurred in many locations along the coast of Korea. Thalli are foliose, simple or broadly lanceolate blades with irregular lobes and proliferations from the margins, sometimes undulate, soft fleshy, and slippery, up to 32 cm tall, and have cystocarps with ostioles on the blade. Plastid rbcL sequences reveal that each of these species is clearly separated from other species of their respective genera. S. apoda was well resolved within the genus. However, C. rotunda was distantly related to other members of the genus, and this result needs an urgent revision of the genus.