Aimed at that research on the impact of double suspended grid on energy dissipation effects in stilling pool is few,through model test of not arranging suspended grid，arranging single suspended grid and double suspended grid,the paper comparatively analyzed the flow pattern，maximum water depth and energy dissipation rate in stilling pool before and after arranging suspended grid.The result showed that when the design flow rate Q is 15 L/s,the flow pattern in stilling pool is more stable and the maximum water depth obviously declines after arranging double suspended grid.When changing the type and number of suspended grids,the energy dissipation rate changes little.