The study on Uredinales of Korea was initiated by P. Hennings in 1899. After that abundant works were done by Naohide Hiratsuka. And Seiya Ito, P. & H. Sydow, K. Nakata, S. Takimoto, A.L. Jaczewsk, V. L. Komarov, W.A. Tranzschel and others also engaged in the research on this field. Since 1956 the author has collected the specimen in South Korea, chiefly around Prov. Kangwon, among which are found 12 species 4 genera of rusts and 22 species of additional hosts all unrecorded from Korea. The author has described in the paper 220 species 32 genera 3 families of rusts in Korea, including those collected, by this author. This works, it must be added, owe much to the literatures of Dr. Naohide Hiratsuka, Prof. of Tokyo University of Education. The author express his hearty thanks to him.