This study surveyed the vascular flora present in 455 forest wetlands in South Korea to provide baseline data for conservation, management, and monitoring and to support preparation for climate change. The survey period was from April 2015 to November 2019. The vascular flora of 455 forest wetlands were identified and were found to consist of 143 families, 582 genera, 1,246 species, 26 subsp., 104 var., 12 f., and 1,388 individual taxa. 8 taxa were identified as Grade II endangered wild plants, 220 taxa were identified as northern lineage plants of the Korean Peninsula, 66 taxa were endemic to the Korean Peninsula, and 94 taxa were rare plants as designated by the Korea Forest Service. Among them, 8 taxa were Critically Endangered species, 10 taxa were Endangered species, 31 taxa were Vulnerable species, 31 taxa were Least Concern species, and 14 taxa were Data Deficient species. Further, 411 taxa were floristic target plants, of which 17 taxa were classified as grade V, 70 taxa as grade IV, 110 taxa as grade III, 90 taxa as grade II, and 29 taxa as grade I. There were 64 invasive alien plant taxa. 18 of these species were classed as Widespread species, 9 taxa were Serious Spread species, 13 taxa were Spread Risk species, 18 taxa were Spread Concern species, and 6 taxa were Continuing Spread species. According to wetland preference, 152 taxa (11.0%) were obligate wetland plants, 138 taxa (9.9%) were facultative wetland plants, and 177 (12.77%) taxa were facultative plants. Additionally, 198 taxa (14.3%) were facultative upland plants, and 723 taxa (52.1%) were obligate upland plants.