Abstract: According to the reservoir characteristics of the Kongdian Formation in Zaoxi area in Dagang oilfield,parameters reflecting the reservoir micro and macro features are selected and reservoir evaluation criteria are established. Comprehensive reservoir evaluation free of influences of artificial factors are carried out through use of fuzzy theory. The reservoirs in this area are lake-floor fan and lake beach bar sandbodies which are closely related with sedimentary microfacies. Water channel deposition and beach bars are the best reservoirs in this area. Reservoir evaluation reveal its distribution pattern and provide reliable basis for development planning and series of strata dividing. Application shows that this technique is practical and feasible.