The problem of eco-environmental construction on the Loess Plateau is avery important and protruding problem in comprehensive control over the loessplateau at present. Based on many years' scientific research and experimental data,the author analysed the urgency of eco-environmental construction of the loess pla-teau, and pointed out the severe damages caused by soil and water erosion on theLoess Plateau. Also, this paper deals with rogional behaviors of eco-environmentalconstruction on the loess plateau with actual examples cited concerning eco-environ-mental construction in such three experimental areas as in Anzai, Changwu andGuyuan counties. This paper finally suggests several key scientific and technologicalproblems needed to be studied urgently.