By the numerical experiments, we clarify the regional wind systems that generate dust storms in the Tarim basin, Northwest China. In the basin, dust storms are generated by a mesoscale cold wind system induced by a synoptic-scale cold air mass behind a cold front. The intruding course of the mesoscale cold wind into the basin can be classified into three patterns. The first pattern is characterized by the easterly mesoscale cold wind, which is separated from the synoptic-scale cold westerly and turns westward after going around the eastern side of the TianShan Mountains. The mesoscale cold wind categorized in the second pattern directly crosses over the TianShan Mountains, which often gives a very strong wind in the basin with the largest dust storms in the three patterns. The third pattern indicates that the cold wind crosses over Pamir plateau, although the magnitude of the dust storm is usually small.