An investigation on avifauna of the Bangtaesan Mountain was carried out from February until November, 2010 and it drew the results as follow. The number of birds observed in the whole Bangtaesan Mountain region was 989 individuals of 51 species (Maximum counts). Considering the results from literature research in addition, at least 90 species 1,000 individuals are thought to live in this region. In result, dominant species proved to be Yellow-throated Bunting (Emberiza elegans), Marsh Tit (Parus palustris), Azure-winged Magpie (Cyanopica cyana), Eastern Crowned Willow Warbler (Phylloscopus coronatus), Varied Tit (Parus varius), and more. Most of birds breeding in the forest of Korea were found to constitute these dominant bird species. Entire species diversity index appeared to be 3.35 relatively a high level; 3.34 in the south slopes while 3.22 in the north slopes showing relatively a high level in the south. Of them, 12 species including Mandarin Duck (Aix galericulata) were the Protected Birds species nominated and protected by the Cultural Heritage Administration or the Ministry of Environment, while 10 and 6 species were the natural monument species and endangered species level, respectively. Should further consistent surveys be carried out, a broader range of species would be found to breed, and therefore the Bangtaesan Mountain region including the area where the protected species are observed is believed to need a conservation and management through protected area designation.