Agro-ecological regionalization is a kind of ecological-economic regionalization. In the article taking the Weibei Dry Plain as an example,analysed the characters of agro-ecological regionalization: 1. comprehensive nature; 2. whole nature; 3. nature of more grade; and 4. no overlap or repetition of ecological units. The principles of agro-ecological regionalization in the Weibei Dry Plain is discussed. The principle of zonal division is basic. The principle of structural identity of physical Landscape, the...