Based on systematically monitoring plants on dune ridges in the southern part of theGurbantunggut Desert in 2002, this paper, from the angle of dune stabilization by vegetation,describes the temporal and spatial distribution patterns of ephemeral plants on isolated sand dunes,analyses the natural invasion processes of ephemeral plants on human-disturbed sand surface andexpounds the importance of ephemeral plants in stabilizing sand dune surface. A total of 45 plantspecies were identified in the study area, 29 of which are ephemeral plants. Ephemeral plantssprouted in early April and completed their life-circle within about two months. Just as aeolian sandactivities came to the strongest stage from April to June in desert regions of northern Xinjiang, thetotal coverage of trees, shrubs and herbs of long vegetational period on most dune ridges was lessthan 10%, while the mean coverage of ephemeral plants reached 13.9% in April, 40.2% in May and14.1% in June. Therefore ephemeral plants acted as the major contributor to dune surfacestabilization in the Gurbantunggut Desert. Investigations of vegetation restoration onengineering-disturbed dune surface show that ephemeral plants first recolonized the disturbed dunesurface.