About 50-year data on water and sediment discharge of the Changjiang River at the Dotong gauge, and observation data on suspended matter concentration collected in 22 cruises in the East China Sea (ECS) were analyzed to study the tendency of water and sediment discharge of the Changjiang River and the temporal variability of suspended matter concentration in the ECS. From the 1950s up to now, the annually average water discharge of the Changjiang River was not obviously variable, while sediment discharge had declined remarkably since 1986 because of the construction of the Gezhou Dam. Suspended matter concentration in the ECS having obviously decreasing trend with time, was consistent with the variability of sediment discharge of the Changjiang River. Furthermore, the reduction of suspended matter concentration at the Estuary and its adjacent sea area was more than that on the continental shelf. The decrease of suspended matter concentration in the sea was not to the same extent as that in the Changjiang River, because the factors that controlled suspended matter concentration in the studied sea area were the material source and the hydrodynamic conditions when in-situ observations were being carried out. Especially in winter, the hydrodynamic conditions sometimes would become the major factor controlling suspended matter concentration.