For the poor quality of rotary jet piles in the sea artificial island environment and the superposition of deep riprap layer，combined with an actual project of the east artificial island of the Shenzhen-Zhongshan Bridge，we carry out a two-stage study on the construction technology of rotary jet piles based on the process test to verify the water stopping effect by water pumping and recovery tests and optimize the subsequent enclosure structure form.The results show that the rotary jet pile construction method combining rotary excavation for filling and rotary spray grouting combined and adopting dynamic control of slurry lifting speed based on theoretical calculation formula is effective，which can effectively solve the construction problems of slurry loss in the riprap layer.The enclosure structure form combining infill pile and inter-pile water stop rotary jet pile can meet the water stop demand of the pit excavation and can eliminate constructing the external waterproof curtain.