In 2011, water conservation projects construction in China entered a stage of rapid growth. In February 2013 three dam safety accidents occurred due to improper participant subject behaviors. Improving security and risk management of water conservation projects is therefore considered as imminent. It is urgent to research the risks of the participant subject behaviors. This article takes each participating subject in the whole life-cycle of water conservation projects as the research object, analyzes the risk behaviors and risk evolution processes, dissects the cause of the risks of the participating subject behaviors on the basis of the theory of risk effect, and puts forward that reinforcing the penalties, improving criminal cost and strengthening the engineering ethics education is an effective way to solve safety problems of the current projects.