A 70cm-sediment core was collected from West Lake, an eupert rophic lake, Hang zhou, P.R.China.Samples were studied by the fraction procedure of Hieltjies & Lijklema (1980) to obtain the phosphorus fractional profiles.In the sediment, the largest partof phosphorus (30%-70%)was bound to calcium, while Fe & Al bound P (NaOH-rP)and loosely absorbed P (NH₄Cl-rP)holding about 16%-40% and 0.6%-10% separately;labile phosphorus comprised of 20%-40% of the particulate phosphorus at the time of deposition.The vertical distribut ion of P fractions and labile phosphorus were similar with that of total phosopho rus.In the deep partof sediment the contents increased with the decrease of depth;the peaks all appeared in the layers of between 10-30cm;while in the upper layers a decline with depth was presented.