为了给农业水资源安全下一个比较明确的定义，同时给出这一定义的内涵和外延，本文在综述水安全、水资源安全、水环境安全3个概念不同的定义，辨析它们之间关系的基础上，推敲了农业水资源安全概念的组成要素，得出农业水资源安全应该是水资源的供应保障农业不受威胁，没有危险、危害和损失。这一定义的内涵包括农业水资源安全的自然属性、社会经济属性和人文属性3个方面。其外延涉及广义和狭义的农业水资源安全，以及由农业水资源安全引发的粮食安全、农业生态环境安全、农业经济安全、农村社会安全等。定义这一概念可以为开展农业水资源安全研究、确定农业水资源安全的理论框架、建立农业水资源安全评价体系提供一定的理论参考。

The objective of this paper is defining the term of agricultural water resources security, its connotation and extension. The definitions of water security, water resources security and water environment security were summarized, and their relations were differentiated and analyzed. Based on these, the elements of the conception of agricultural water resources security were hashed and the conception was defined. Agricultural water resources security should be that water resource provision ensures agriculture against threat, hazard, harm and losing. Moreover, the connotation and extension of agricultural water resources security were ascertained. In detail, the connotation of the definition has natural attributes, socioeconomic attributes and human cultural attributes. The extensions include broad and narrow sense, as well as, food security, agro-environmental security, agro-economic security, rural society security, etc due to agricultural water resources security. The definition will be the frame of reference for developing the researches, limiting the frame of the theory, and founding a appraising system for agricultural water resources security.