In this paper, risk theory has been used in the management of water resources during drought period, and the corresponding indexes such as risk, reliability, resiliency and vulnerability have been given. In practice, these risk indexes can reflect the real detrimental level of drought from different aspeects.The method is simpler than system optimization, and is more convenient for water resources administrator to formulate and choice effective measures for drought management. This study can provide a new way for planning and management of water resources.