Abstract: Fluvial sandstone reservoir is in high water cut stage,both plane and level contradiction are further highlighted,water drive results are become worse and worse. The urgent problems in reservoir exploitation are how to identify and block off dominant flow channels. By taking the reservoir in the first section of Guantao formation,Chengdao oilfield as an example,a set of comprehensive evaluation methods for rapid identification of dominant flow channels were formed by means of index calculation method,water absorption and liquid production chart method,and dynamic analysis. On the basis of channels identification,the adjustment direction is indicated. Increase the production and injection of the wells in non-dominant channels,and decrease the production and injection of the wells in dominant channels. The underground flow field will be balanced by expanding swept area. Good field application effect has been achieved and it is of great significance for the further waterflooding development of Guantao formation.