The reservoir，wellbore and pipe network are major links in a development and production system of oil and gas fields. Traditional numerical simulation methods mainly simulate the fluid flow in the reservoir，while the coupling simulation based on reservoir-wellbore-pipe network integration reflects fluid supply capacity of the reservoir，lifting capacity of the wellbore，and gathering and transportation capacity of the pipe network at the same time. It is of great significance to accurate prediction of the production situation and the whole process optimization of a production system. By studying the construction method of a wellbore-pipe network model and the adaptability of multiphase pipe flow correlations，we realized the flow simulation and flow assurance simulation in the wellbore and the pipe network. An integrated model was built through node links，and the flow relationships between key nodes were coupled to develop a coupling simulation method based on reservoir-wellbore-pipe network integration，enabling the whole process simulation of oil and gas field development. In the West A Block of Chengdao Oilfield，the production system，proration，injection allocation，and other aspects were optimized according to the actual production demand and constraints of offshore oil fields. In addition，the whole process optimization based on the integration model maximized the production benefit of the oil and gas field development system.