Abstract: According to the comparative measurement of 8 snowfalls by using the methods of precipitation gages and snow survey on the ground in a small alpine watershed of the Urumqi River Basin during the period between Oct. 1989 to May-1990, it is found that the Chinese standard precipitation gages catch 73% of the relative ground true snowfall. Therefore the snowfall measurement of the gage has a poor representative to the basin-wide snowfall. This systematic error caused by wind effect on the gage should be corrected first for water budget calculation and snowmelt runoff simulation in mountain area.