Abstract: In order to solve the problem that the weak water drive viscous oil reservoir HJ2-21 in EP18-1 oilfield in the Pearl River Mouth Basin could not maintain normal production soon after been put into production due to insufficient producing energy, a single well production-injection integration technology was proposed based on the reservoir recognition and that there was no water injection equipment in the platform, the single well production-injection integration design was then conducted based on the water compatibility, sand control design, string design, downhole data monitoring. Single well production-injection integration technology has been experimentally tested in the viscous oil reservoir in EP18-1 oilfield with great success and economic benefits. It also provided experience for the development of similar oilfields.