Pressure-state-response (PSR) model were applied on ecological security assessment in 22 major reservoirs of Henan Province so as to manage the ecological environment of reservoir watershed and protect the water quality. The index system of reservoir ecological security was built, the weight of each index was determined by the method of entropy value, and the station of ecological security of 22 reservoirs was evaluated by the method of ecological comprehensive index in 2005 and 2015. The results showed that: generally, the ecological composite index of reservoirs in 2015 was significantly higher than that in 2005, but the situation was not optimistic because the composite index of 22.73% reservoirs was below 0.4. The level of economic development was not directly proportional to the ecological security of reservoir, and the ecological environment of the reservoir was often poor in the area of economic developed. We conclude that: PSR model can also be adopted in the environmental ecological safety assessment of large scale and many reservoirs. We should also care for the environment while developing the economy, in order to achieve harmony between mankind and nature.