Abstract: Reservoir heterogeneity is a key factor to find remaining oil and enhance oil recovery in the later stage of production.Guided by the theory of fluviatile sedimentology，based on the present deposition and outcrop survey，we studied the upper reservoir of Guantao Group in Gudao Oilfield with abundant well logging data from the dense well network and reservoir architectural structure analysis method.The researches lead to the conlusion that the upper reservoir of Guantao Group in Gudao Oilfield can be divided into ten levels theoretically，and in our study reservoir has been divided into seven levels，from which seven architectural factors such as main stream channel，abandoned channel and crevasse channel etc.are identified.The method of building architectural model that focuses on retrieving single channel sand body is summarized on the basis of fine reservoir comparison.The significance of this geologic structural model to oilfield development is also discussed.

Key words: fluvial reservoir, identify, single channel, genetic sandbody, Gudao Oilfield