The safety management of the small reservoirs is the weak link of water conservancy project management.In order to improve the management level，it is important to classify the safety level of small reservoirs and to adopt classified management.In this paper，according to the safety status of small reservoirs， we used AHP and Delphi method to build the risk index system of the small reservoirs，and defined the classification principle of each index，then puted forward the risk classification calculation method of small reservoirs.40 small reservoirs are selected and the risk classification is carried out according to the risk classification calculation method we builded.The calculation result was consistent with the actual situation of the small reservoirs，which shows that the method has strong applicability，and lays a foundation for carrying out the classification management of small reservoirs in the future．