Abstract: Based on the surface observation data and FNL data （horizontal resolution was 1.0°×1.0°,time interval was 6h）,a snowfall processes occurred on February 18 and 19 2014 in Hohhot was analyzed in the aspect of circulation pattern, physical quantity field and others.The results showed that the synergistic effect of high altitude short wave trough moving to east,the shear line existing in middle and low level wind field and the ground inverse trough provided a favorable circulation pattern for the snowfall processes.The upper level divergence,low level convergence and strong ascending motion provided favorable dynamic condition for the vertical transport of water vapor.Furthermore, the warm moist air extending from south to north to Hohhot accumulate an amount of instability energy for the snowfall.