Abstract: The paper was taken example by the flux of heavy metals (Pb、Cu、Zn、Cd ) into the sea, with the consideration for the actul status of the Poyang Lake River, to estimate the flux out of the lake by the five rivers of the flux of heavy metals and heavy metals into the lake, and according to history and status of heavy metal pollution in the Poyang Lake, to determine other ways to enter the lake through the heavy metal flux. It was found that the different composition of the different heavy metals out of the lake, Cu, Zn, Cd was mainly dissolved, and Pb mainly in the suspended form; into the sea by tidal flux method when calculated total flux of the river into the lake below the heavy metal heavy metal flux out of the lake, compare with the flux into the lake are Pb> Cu> Zn> Cd, for surface runoff, lake water discharge, rainfall, and other heavy metals enter the endogenous pathway to release a greater impact, should strengthen the monitoring, Poyang Lake water to prevent the intensification of heavy metal pollution.