This study investigated the vascular flora in Deoksan Provincial Park, located in Yesan-gun, Chungcheongnam-do, based on 12 field surveys conducted from May 2024 to July 2025. The survey identified a total of 439 vascular plant taxa, comprising 108 families, 273 genera, 404 species, four subspecies, 29 varieties, and two forms. Among them, 14 taxa were Korean endemic plants, and six taxa were included in the red list of plants. The floristic regional plants comprised 54 taxa, including three taxa of grade IV, 12 taxa of grade III, 15 taxa of grade II, and 24 taxa of grade I. A total of 156 taxa were identified as biological resources subject to approval for overseas export, and 8 taxa were identified as climate change indicator plants. Additionally, 55 taxa of alien plants were identified, resulting in a naturalization rate of 12.5% and an urbanization index of 8.8%. Two taxa of ecosystem-disturbing species were found to be distributed in the area. This study provides foundational data for the efficient management and operation of Deoksan Provincial Park and is expected to serve as baseline information for biodiversity conservation and the systematic management of plant resources by identifying the current status and changes in its flora.