This basic study is to present the methods and raw data for carrying out to objectively assess an ecosystem by developing the plant ecological indices. The results are as follows. The plant ecological indices were 7 units including RI (Rare Index), EI (Endemic Index), SI (Specific Index), NI (Naturalized Index), UI (Urbanized Index), Pte-Q (Pteridophyta Index) and HI (Halophytes Index). The vascular plants in Mt. Waryong, Mt. Bongmyeong and Bito island were summarized as 471 taxa including 104 families, 294 genera, 419 species, 3 subspecies, 41 varieties and 8 forms. We surveyed 5 taxa of rare plants, 7 taxa of endemic plants, 38 taxa of specific plants by floristic region, 40 taxa of naturalized plants, 1 taxa of invasive alien plant, 19 taxa of pteridophyta and 14 taxa of halophytes. Bito island had the highest RI was 1.2%. Mt. Bongmyeong was 1.4% higher than other sites. If the SI of 2.9% was the highest in Bito island. Bito island was the highest NI, and the UI was the hightest in Mt. Waryong. Mt. Bongmyeong was the lowest NI and UI. In Mt. Waryong and Bito island, the highest DI was 9.1%. The Pte-Q of Mt. Waryong was 1.3 higher than the other sites. Bito island, the highest HI was 8.1%. Overall, 1.5% of RI, 1.9% of EI, 2.3% of SI, 8.5% of NI, 14.3% of UI, 9.1% of DI, 1.0 of Pte-Q and 3.0% were analyzed with HI.