On the basis of existing operation plan of the Three Gorges reservoir, the operation condition and controlling factors of flood control, power generation, and navigation of the reservoir running were analyzed. According to the economic and social development needs in Yangtze River basin and recently continual emergence of drought and water shortage problems, the drought situation in middle and low Yangtze River area and the demand to the Three Gorges Reservoir operation were discussed. The capacity of the Three Gorges Reservoir to solve drought defying and possibly existing problems were analyzed. Finally, some suggestions for the drought defying operation of the reservoir and the comprehensive measures to resist drought were put forward. It has been shown that the Three Gorges Reservoir to increase drought function is necessary, but operation condition must be studied and the benefit evaluation system for drought defying needs to be set up.