We carried out vegetation analysis of Evergreen Broad-Leaved Forests(EBLF) in three islands(Gageo-do; GGD, Hong-do; HD, Heuksan-do; HS) of S. Korea. With phytosociological analysis and DCA for vegetation analysis, It was carried out that comparative study about similarities among study areas by Total Constancy Value(TCSV) and Quantitative Common Coefficient(QCC;%), based on the vegetation data of three islands and other areas(Jeju-do(JJ), Islands in southern part of Korea(ISK), Tsushima(TS) and Northwestern part of Kyusyu in Japan(NKJ)). As results, EBLF of three islands is composed of four forests: 1.Quercus acuta, 2.Machilus thunbergii, 3.Carpinus turczaninovii and 4.Castanopsis sieboldii. The highest value is the QCC between HD and HS(80.26%), and the second and third are between GGD and HD(71.77) and between GGD and HS(66.85) in the similarity among three islands. We think the correlation between distances and the QCC exists. Even the QCC among HD, HS and Japan(TS, NKJ) are higher than the one between GGD and Japan, GGD is more similar with Japan in flora because some species growing wild only in Japan such as Viburnum japonicum were found in GGD.