The landward changes of soil enzyme activities and physico-chemical properties of the surface sediments in the east end of Chongming Island, in the Yangtze river estuary, were studied. Along the elevation gradient or succession sequence, the contents of total phosphorus (TP), total nitrogen (TN) and organic matter (OM) of sediment increased, but the average grain size (AGS)and dissolved inorganic phosphorus (DIP)decreased. The activity of alkaline phosphatase increased gradually along the elevation gradient, and was positively correlated with the values of TP, TN and OM (p<005), but negatively to AGS and DIP(p<0.01). Alkaline phosphatase activity was correlated with a mechanism of substrate inductivity and product inhibition. Catalase activity had the similar trend of gradual elevation increase and enhanced the fertility of the soil and oxidative process of OM in the sediment. From the succession zones, bare flat to bulrush(Scirpus mariqueter) to reed (Phragmites australis), the activity of sucrase changed only insignificantly but the bulrush zone had a higher activity than others. The activity of proteinase decreased from bare flat to reed zone and the activity was negatively correlated with OM and TN (p<0.05), but positively with DIP (p<0.05). Through the succession zones a decrease in number of diatoms resulted in a decline in the concentration of protein, which influences the proteinase activity, suggesting that the proteinase in the sediment was produced by diatom.