Coastal regions are important habitats for migratory shorebirds. The aim of the study is to understand the habitat use by the migratory shorebird and to develop a conservation strategy in sustainable-use of wetland and the migrants. From March 2004 to January 2005, we conducted seasonal shorebirds censuses in ten coastal habitats along the south Yangtze River mouth and North Hangzhou Bay, examining the relative seasonal abundance of shorebirds and their spatial distribution simultaneously. A total of 25 species were identified, the seasonal dominant species were Great Knot (Calidris tenuirostris), Sharp-tailed Sandpiper (Calidris alpine) and Red-necked Stint (Calidris ruficollis) in spring; Kentish Plover (Charadrius alexandrinus), Common Greenshank (Tringa nebularia) and Lesser Sand Plover (Charadrius mongolus) in summer; Kentish Plover, Red-necked Stint and Common Greenshank in autumn; Dunlin (Calidris alpine), Kentish Plover and Marsh Sandpiper (Tringa stagnatilis) in winter. These species accounted for more than 85% of all shorebirds counted. The numbers of shorebirds counted were highest in spring and then in autumn, winter and summer consequently. Among the four seasons, there were little significant differences of bird species abundance between the sites outside seawall (natural mudflat) and the sites inside seawall (artificial wetland), but the average density of shorebirds had obvious difference. The habitat-selection analysis of the environmental-factor (outside and inside the seawall) impacting on the shorebird community was made in the ten study sites with Canonical Correspondence Analysis. The study results indicated that: (1) Outside the seawall, total intertidal the widths of intertidal mudflat and bare mudflat were the key factors affecting the shorebirds; the proportion of bulrush (Scirpus×riqueter) covering and supertidal mudflat width had the positive correlation with the bird abundance, the human disturbance and the proportion of reed (Phragmites communis)/smooth cord-grass (Spartina alterniflora) covering had the negative impacts on the bird contribution; (2) Inside the seawall, mudflat with sallow water and the proportion of mudflat were the key factors to increase the bird abundance; the proportion of bulrush covering should benefit to the shorebird appearance. The habitats with heavy human disturbance, dense reed and smooth cord-grass bed or high water table were not good to be used by shorebirds.