Abstract: According to different oil viscosity, the water flooding reservoir in Bohai oilfield is divided into low viscosity, medium and high viscosity, normal heavy oil(grade Ⅰ-1) and normal heavy oil(grade Ⅰ-2). Aiming at different types of water flooding reservoirs, typical development units are selected to calculate the actual curve of the relation between water content and recovery degree, and the normalization process is carried out. By using Wanjiye water flooding curve for quantitative fitting,the curve chart of relation between water content and recovery degree of different types of water drive reservoirs is established to reflect the difference of increasing regularity of water content in different types of water flooding reservoirs. The relation chart has been successfully applied to the evaluation of development effect of nearly 50 water flooding reservoirs in Bohai oilfield and the evaluation results are objective and accurate, which can truly reflect the actual development level.