In recent years，intelligent separate injection-production techniques have been playing a very important role in improving the water-flooding development effect of reservoirs. For the evaluation of the improvement in water-flooding development effect，a set of quantitative comprehensive evaluation method is established considering the influencing factors such as physical properties of reservoirs，fluid properties，recovery，and development performance. Firstly，common evaluation indexes are classified and the selection principle is determined to sort out nine typical evaluation indexes according to the logical analysis method. Then，the comprehensive weights of evaluation indexes are determined through grey relational analysis and analytic hierarchy process with recovery factor taken as the objective function. On this basis，according to the existing industry standards for the grading of oilfield development levels，the grading scoring standards at different crudeoil viscosity and water-cut stages are established. The comprehensive score and score difference before and after the application of the intelligent separate injection-production technique in the target oilfield are calculated. The score difference represents the improvement in water-flooding development effect. A greater score difference means a better improvement in water-flooding development effect and a higher producing degree of the remaining oil. The results of numerical simulation also show that there is a positive correlation between score difference and increased oil production.