By using the meteorological monitoring data, the meteorological causes for the massive mudslide in Zhouqu which occurred on 8 August 2010 are analyzed. Results demonstrate that the severe convective weather process with heavy precipitation is the main cause for this massive mudslide. The characteristics of this heavy precipitation are local, large intensity in short time and paroxysmal. The data of radar and satellites suggest that the weather system has obviously mesoscale characteristics. This kind of mesoscale weather system is produced by the forcing of the shear line in the low level, when the cold air in the high level is moving eastward and southward.