Abstract: The changes in water balance and nitrogen metabolism of sandfixing plants under soil drought condition in desert area were studied. During sustained drought, the free water content was decreased and the bound water content was increased in all of the experimental plants. Nitrogen metabolism in the plants was converted by drought. The protein synthesis was inhibited, in the meantime the non-protein nitrogen was accumulated. It was found that a notable difference exists in various plants as far as accumulated non-protein nitrogen is concerned, amide nitrogen was accumulated mainly by xerophyte Hedysarium scoparium and nitrate nitrogen by mesophyte Robinia psudoacacia. The water balance of plants and the role of bound water in drought resistance are also discussed.