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Monitoring studies show that many Mountain glaciers worldwide are decreasing in mass. An important component of the process of ice mass loss is the effect of dust oil albedo and its effect oil glacier mass balance. The characteristics of surface dust were investigated in August 2006 oil the Urumqi Glacier No. I in the Tien Shan Mountains, China. The bare ice surface of the glacier was mostly covered by brown dust. The amounts of surface dust on the ice surface (dry weight) ranged from 86 to 1113 g m(-2) (mean: 335 g m(-2), standard deviation: = 211). which is within the normal range for Asian glaciers, but significantly greater than those on glaciers in other regions such as Alaska. Patagonia, and the Canadian Arctic. Ail analysis of organic matter and microscopy of the surface dust revealed that the dust contained high levels of organic matter, including living cyanobacteria. This suggests that it is comprised not only of deposits of wind-blown desert dust, but is also it product of microbial activity oil the glacier itself. Spectral albedo of the glacial surface showed spectrum curves typical of those of snow and ice contaminated with dust. The integrated surface albedo ranged from 0.09 to 0.24 (mean: 0.14) in the ice area. from 0.50 to 0.64 (mean: 0.56) in the snow area. The lower albedo oil the glacial surface compared with that of clean bare ice or snow surface suggests that the albedo was significantly reduced by the surface dust oil this glacier. Results Suggest that the mineral and organic dust oil the glacial Surface Substantially accounts for the recent shrinkage of the glacier.