When the underwater concrete is poured by tremie method,the exposed reinforcement accident is often caused due to the inadequate accuracy control of the lifting tremie of the crane,which affects the safety and economy of the project.The theory of trench stability during underwater concrete perfusion is proposed to improve the construction quality of underwater concrete perfusion and reduce necking accidents.Based on a multi-purpose berth project in Jingtang port area,a new type of underwater concrete pouring equipment is developed,and design concept,structure and operation process of the equipment are summarized.The actual project shows that the effect of diaphragm wall surface after excavation is better by using this equipment to pour underwater concrete.The relevant technology can provide reference for similar projects.