Abstract: Deepwater drilling conductor is usually run by special jet-in technique. The design method of borehole structure design method for deep exploration well is quite different with that in shallow water and onshore drilling. In order to finish the design of Qiongdongnan deep exploration well, on the basis of geological environments, the difficulties, challenges and design principles of deep water borehole structure design have been considered fully, and simulation calculation for detailed conductor setting depth and design of surface technical casing have been conducted for Qiongdongnan deepwater drilling. The design scheme for deep water wellbore structure in Qiongdongnan basin has been decided, and this design method can provide experiences and references for Qiongdongnan deepwater well borehole structure design.