Abstract: At present, the drainage sluices along the Qiantang River estuary are mainly concave on the seawall, the width of sluice is only about 0.60～0.85 of the width of upper channel. Due to the strong tidal and high sediment concentration characteristics at the Qiantang River estuary, it is easy to cause serious siltation under the sluice, and the local scouring is serious. Moreover, the scale of upper river reach is usually insufficient to give full play to the drainage function of these sluices. To solve these problems, combined with author's practical experiences and previous research results, it was proposed to set additional storage facilities before the sluice, and the sluice axis was placed in line with the embankment line. It can effectively improve the drainage capacity of the drainage sluice while ensuring the safety of the project, and it is conducive to improve the ability of disaster prevention and mitigation in the region, and provide guarantee for local social and economic development. The results can be used as reference for the design of similar tidal estuary drainage sluices.