Based on the conditions of flood-releasing hydraulic，topograph and geology , wing walls of two bank and embankment safety, construction and investment etc.，one or two stages of stilling basin can be chosen in the downstream of barrage. The paper analyzed the layout and hydraulic calculation method of two stages stilling basin in downstream of sluice that are first, determining the horizontal bottom's elevation of primary stilling basin , and then calculating the reasonable height of stilling basin end sill and horizontal section length which can form stable hydraulic jump in stilling basin;secondly, according to the river water level conditions at the downstream of sluice, and meeting two stages stilling basin flow joint with the downstream river flow in subcritical flow conditions, protocoling preliminarily the top elevation of the second stage stilling，and then calculating the depth and length of stilling basin.which make stilling basin out flow joint smoothly with downstream river flow. The results verified by hydraulic model test of the examples can provide a reference for similar engineering design.