Abstract: Comb slideway well beam is a complex process in water transportation engineering,with high precasting accuracy,large volume,irregular bottom geometry and many edges and angles. There are few similar projects,and there is a lack of relevant reference experience. In order to ensure the geometric shape of the shaft beam during underwater installation,the construction concept of matching short and medium lines of bridge engineering is applied to the prefabrication of slideway well beam. Good application results have been obtained. The storage area is arranged and the bearing capacity of the foundation is checked. A suitable support system and formwork system are designed and applied,and the support system is reviewed,and the force meets the requirements. Three-way jacks are used to review the formwork data during each prefabrication of the well-shaped beam,which greatly improves the precast accuracy of the well-shaped beam. The inner template with automatic opening and closing is designed and applied. The rapid opening and closing of the template is realized under the action of the template’s own weight,and the construction efficiency is improved. It can provide reference for prefabrication of chute well beam.