Abstract: The conception and definition of ecological 1and use in arid area in Northwest China are stated in this paper．The ecological 1and use is divided into two categories，of which one is an artificia1 type including agricultural oasis and township oasis，and another is a natural type containing naturally preserved area ，water-conserved forest in mountainous area，natura1 oasis，wetland，desert vegetation area and wasteland．Meanwhile，the service function of each type of ecological land use for the main ecosystem is introduced．Finally，it is put forward that the research on ecological land use should be focused on the three aspects：developing evaluation of ecological land use resources aiming at its quantity，quality and spatial distribution；identifying the rational proportions of ecological land use in total area and in the different water-sheds in arid area in Northwest China；quantifying the relationship between ecological land use and ecological water use．