Abstract: It is required to conduct debugging on water cycle in offshore production system during the stage of platform construction and to simulate normal production process in order to verify the integrity and function of the offshore oil production system.In the production platform in nature gas field,the pressure in production system is high,and there exist gas-liquid two-phase at same time.Therefore,the condition for debugging on water cycle system is very harsh,and technical requirements are very high.From the point of safety,feasibility and economic of debugging on water cycle system in nature gas production platform,field practice has been conducted in simulation of water cycle debugging on in offshore production system in Lishui 36-1 CEP nature gas production platform.The debugging scenarios have been optimized from the connection way of temporary pipes,adding scenarios of nitrogen and testing scenarios on instruments function.It is expected that this can provide a guidance and reference for debugging on water cycle in this type of offshore oil production system.