By means of the fuzzy grading method, the ensemble area rainfall forecast and the three prediction models used in the area rainfall prediction over the Three Gorges Reservoir Valley (analogy forecast, MM5 model and T213) are assessed comprehensively. The results show that the prediction accuracy of the analogy forecast method is about the same as those of MM5 model and T213 rainfall prediction, and the prediction accuracy in winter is better than in summer for all the three prediction models. In practice, the dynamically weighted coefficient method is adopted in the integration of the three prediction models, to make full play of their advantages. The integrated forecast performed better than the three methods. It is proved that the fuzzy assessment method of drainage area rainfall can be used in quantitative rainfall forecast assessment because it can reflect objectively the difference between predicted and actual rainfall.