For the development of offshore horizontal wells, the study of remaining oil should be based on clear main control factors. Research on residual oil distribution under main control factors by numerical simulation method,the research showed that for the oilfields which developed by horizontal wells predominantly, the main controlling factor of remaining oil should be clear as the basis of numerical simulation. in this paper, both the position and digging direction of the enrichment of remaining oil were summarized, it also gives the conclusion that physical conditions, sedimentary microfacies, interlayer, development method were the most important influence factors on remaining oil which characterize the oilfield. Among them, the remaining oil in the interlayer interlayer and multi⁃stage river channel superposition control is the heaviest, which is the main target for future adjustment and potential tapping.

        In order to effectively and rapidly develop the offshore fluvial faces oilfield, the development pattern of the oilfield is investigated from four aspects which are based on the features of geology and development for Bohai Y oilfield. The four aspects include, fine water injection to maintain formation pressure, combine and divide layer series of development by single sand body, well pattern optimization technology for single sand body and comprehensive adjustment by combining water extraction and water control. Development effects for each single development index developed at the development pattern of Bohai Y oilfield are calculated by reservoir engineering methods. Then the comprehensive development effects are evaluated. Results manifest that, development pattern of Bohai Y oilfield is suitable for most offshore fluvial faces oilfield. The development period  can effectively shorten the development period of offshore oil fields and improve the ultimate recovery of oil field by applying this development pattern.