Abstract: In recent years, deepwater is increasingly becoming the hot region for global oil and gas exploration and development. Compared with onshore or shallow-water oilfields, deep-water oilfields development usually has characteristics such as expensive investigation, long construction period, high geological risk, and demanding complex techniques, etc. It is a great challenge to perform high-efficiency development for deep-water oilfields. This paper took a certain large deep-water oilfields group in lower Congo Basin as an example, analysed and summarized the main practices and effects of high-efficiency methods used in development. The results show that, using methods such as co-development and high-productivity with less wells, combining with techniques including multi-points geo-statistics modelling under sparse well pattern, integrated optimization of reservoir-wellbore-subsea system, and 4D seismic, high-efficiency development of deep-water oilfields is achievable. The research results have certain reference and enlightenment significance for the development of deep-water oilfields in China.