This study was conducted to clarify community characteristics of waterbirds migrating to Seamangum area from 2002 to 2009. Total maximum count of waterbirds observed at Saemangum area was 686,337 individuals of 176 species. 158 species and 548,989 individuals were recorded on Mangyung Estuary and 158 species and 213,794 individuals were recorded on Dongjin Estuary. Dominance species were Baikal Teals Anas formosa (40.80%), Great Knots Calidris tenuirostris (18.03%), Mallards Anas platyrhynchos (11.67%) and Dunlins Calidris alpina(6.02%). Shorerbirds were declined and waterfowl were increased during survey periods. Natural monuments and endangered birds were 27 species.