Abstract: The Extended Reach Drilling project in Xijiang Oilfield of South China sea is a very successful example of offshore development projects in China, and it also explores a new way for efficiently developing the offshore margin oilfields. Based on the engineering data of 6 drilled ERD wells and together with some theoretical analysis and scientific calculation, the technical characteristics of ERD drilling and completion are analyzed and summarized, while the successful experience is also presented. The main study contents involve such technologies as well profile and casing program design, downhole torque/friction prediction and control, well trajectory control, wellbore stability and hole cleaning, casing running operation, bit selection and corresponding completion and production techniques. Besides the support of scientific theory basis, these drilling and completion techniques are also proven successful in field application.