Abstract: By integrating Type C water-drive characteristic curve with the exponential decline forecast model,one method of resultant is presented,which predicts the development inde- xes during the decline period of water-drive oil field.The method overcomes respective faults of Type C water-drive characteristic curve and the exponential decline forecast mod- el in dynamic prediction.The faults include that Type C wa- ter-drive characteristic curve cannot predict the relations between development indexes and development time.and the exponential decline forecast model cannot predict the water cut,produced liquid capacity,water yield,cumulative water yield and cumulative liquid production.Meanwhile.the method of resultant is adopted to predict the water drive de- velopment indexes of the layer series of development among the basic well pattern at Sabei development area.Results suggest that the new method is practical and effective.