Abstract: The analysis on of grain size distribution characteristics of sand dunes sediments was one of the major content of aeolian landform process.Through the field research and measurement,samples of river sand dunes in the Xiangshui River situated in the west of western Liaohe River campagna were collected along the prevailing wind direction; the grain size distribution law was studied by lazer particle analyzer.The results were obtained as follows:① the grain size of river sand dunes in the east is coarser than that the west.The grain size of river sand dunes in the east decreases from windward slope toe to the mid-below part of leeward slope; the sorting becomes much better from the bilateral slope toe to the slope top.The grain size of river sand dunes in the west becomes finer,equally sorted and positively skewed from the bilateral slope toe to the slope top.River sand is the finest; its mean grain size is finer than the sand in the east and west bank,its sorting is better than the sand in the east bank and worse than the sand in the west bank in general.② With the action of wind and river,sand dunes in the east can get sand source from deep strata.But sand dunes in the west obtain sand of shallow strata under the effect of wind.

Key words: grain size composition, grain size parameters, windward slope, leeward slope, Xiangshui River, Liaohe river plain