Based on analysis of the variation of grain transportation and virtual water flow between southern and northern China, a number of potential crises that could be created by the North-to-South Water Transfer Project with regard to virtual water of grain are described: exacerbation of water stress in the northern regions, threats to national food security, and a widening economic gap between the southern and northern regions. Based on the technical level of water use during grain production and current status of water-saving agriculture, we put forward two suggestions: (1)strengthening the macro-control function of the government, implementing the policy of compensation for water use during grain production, tapping the potential of water-saving agriculture, and alleviating the pressure of water resources for grain production in northern regions; and (2)developing modern water-saving agriculture by introducing market mechanisms, establishing relevant policies as soon as possible in order to encourage and support the investment and construction of water-saving enterprises as well as the operation and management of water-saving agricultural projects, and mobilizing various resources in order to promote the development of water-saving agriculture and guarantee national food security.