Spatial distribution characteristics of total salt content (TS), ion components, exchangeable sodium percentage (ESP) and pH in the mudflat of North Jiangsu Province were investigated using conventional statistics and canonical correspondence analysis. Results show 1) the soil is slight to moderate in alkalization, e.g. moderate in topsoil (0~40 cm) and slight in subsoil (40~120 cm); 2) Na⁺ and Cl^-, K⁺ and Mg²⁺ are well correlated in all soil layers; 3)Cl^-, SO₄^2- and Na⁺ are the main factors controlling spatial distribution of soil total salt throughout the profile, which though varies slightly from layer to layer, Na⁺ remains to be one of the main factors; 4) the spatial distribution of ESP in the whole profile is restricted by CO₃^2-and HCO₃^-, with the former affecting ESP mainly in the soil layers of 0~10 cm and 20~40 cm and the latter in the soil layer of 10~20 cm. However, in the soil layer of 40~100 cm Na⁺ is still the dominant one; 5) In the whole profile pH is more evenly distributed and slightly affected by salt ions.