Comprehensive controlling soil and water loss on the loss plateau has made great achievements since 1949, but there are some problems which should not be neglected: ( 1) The harnessing effect mainly focused on the important regionsand typical watershed, the overall degree of controlling is not good, the total controlling level is quite low, the speed of harnessing is not quick|( 2) The density of population on the loess plateau is far exceed the reasonable capacity there, the contradiction among population, farmland forestry and grain is marked,the controlling on loess plateau made the solving food problem ( dressing warmly and eating fully, etc. ) as its effect|( 3) The purely government conduct and freeinvestment pattern are not beneficial for improving the comprehensive controlling, beside that, the harness policy on loess plateau and enforcement principle have not been thought with the native social, economic and cultural background as a whole, in other word, we have not converted the controlling into the conscious action of native masses themselves, so the results are not good, eco-environment is getting from bad to worsen, so serious soil and water loss and poverty are still the main obstacles for developing society and economy there. In order to put an end to the backwardness of loess plateau, we must change our controlling thought reconstruct the new controlling pattern, the most important measurement is reconstructingeco-system.