This study investigated the characteristics of fish communities and inhabiting status of endangered species in the Bukcheon (Stream) of Seoraksan National Park, Korea from April to September 2020. A total of 4,356 fish of 7 families and 22 species were collected from 17 survey stations during the survey period. The dominant species was Zacco koreanus (relative abundance, 41.8%), and subdominant species was Rhynchocypris kumgangensis (relative abundance, 15.1%), followed by Pungtungia herzi (10.1%), Pseudopungtungia tenuicorpa (5.0%), Coreoleuciscus splendidus (4.1%), Zacco platypus (3.8%), Microphysogobio longidorsalis (3.5%), and Hemibarbus mylodon (2.2%). Among the fish species collected, 14 species (63.6%) were identified as Korean endemic species. There was one natural monument species (Hemibarbus mylodon), and four species of class II endangered wildlife that were designated by the Ministry of Environment (Acheilognathus signifer, Pseudopungtungi tenuicorpa, Gobiobotia brevibarba, and Brachymystax lenok tsinlingensis). Among the four species of class II endangered wildlife, B. lenok tsinlingensis inhabited in the upper stream, and A. signifer, P. tenuicorpa and G. brevibarba inhabited mainly in the middle-lower stream. Also, P. tenuicorpa, H. mylodon, and B. lenok tsinlingensis were inhabited in large numbers. Additionally, two cold-water fish species (R. kumgangensis and B. lenok tsinlingensis) and one landlocked species (B. lenok tsinlingensis) were collected. According to the results of cluster analysis, the dominance index decreased from upstream to downstream, but the diversity, evenness, and richness index increased; the cluster structure was divided into the uppermost, upstream, midstream, and downstream. The water quality of Bukcheon was evaluated as good overall since the river health (index of biological integrity) evaluated using fish was evaluated as very good (11 stations), good (2 stations), and normal (4 stations). However, river repair work was being carried out in some areas and some wastewater was flowing in from the midstream, therefore, supplementary measures to preserve fish habitats are required.