The purpose of this study was to suggest management plans for the conservation of avifauna in Ansan Reed-Wetland Park near Sihwa Lake in Korea. To assess avifaunal biodiversity, the site was surveyed eight times from April to November 2013, and a total of 37 families, 111 species, and 2,929 individuals were observed. The dominant species was Paradoxornis webbianus, and 11 natural monument species were found (Aix galericulata, Platalea minor, Falco tinnunculus, Falco peregrinus, Accipiter gentilis, Accipiter soloensis, Accipiter nisus, Gallicrex cinerea, Otus scopos, Bubo bubo, and Ninox scutulata). Nine species classified as endangered by the Ministry of Environment were observed: two Rank I species (P. minor and F. peregrinus) and seven Rank II species (Falco subbuteo, A. soloensis, A. nisus, A. gentilis, G. cinerea, Charadrius placidus, and B. bubo). The number of species observed in spring (April to May) was higher than that in summer and autumn, and the greatest number of individuals (1,795) was recorded in November. Furthermore, the biodiversity index (H") was the highest (2.887) in June, while the richness index (eH") peaked in May (9.514). Seventy-one species were potential breeders. For the conservation of breeding and overwintering birds in Ansan Reed-Wetland Park, we suggest two-way management strategies to minimize the disturbance of birds during the breeding season (April to July) and of migratory birds during winter (November to March). We also suggest the establishment of a separate, open area for visitors and protected habitats for birds. The separate, open area would serve to educate visitors and reduce human disturbances. Moreover, the planting of fruit trees near the boundaries of the protected habitats would supply food, while minimizing human disturbances (e.g., noise and dust from construction vehicles). These management plans would ultimately help in establishing additional protected wetland habitats.