The agricultural ecological and economic security of watershed means that a sort of situation which satisfy sustainable development of ecological economy of the watershed,containing 3 levels of contents and 3 important characters.According to the current status of the watershed in the loess hilly and gully region,the situation of agricultural ecological and economic security of the watershed can be divided into 4 grades: security,sub-security, insecurity,extreme insecurity,a majority of the watershed has been under the state of sub-safety or insecurity;Take Zhifanggou valley as an example,the author analyses the practical performance of the system in sub-safety situation.Researching on the main problem caused by the system in the situation of sub-safety or insecurity,the author put forward the countermeasures and suggestions: Developing ecological agriculture with commodity economy,and consolidating the coupled relation between industry and resources;Adjusting industrial structure and advancing industrial optimize and upgrade;Building up early-warming system of agricultural ecological and economic security of the watershed,and adjusting input of matter and energy outside the system in time.