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By using the reanalysis data of NCEP/NCAR and the historical meteorological data of 14 cities in Guangxi, the corresponding weather systems of 233 haze days from 2009 to 2013 in Guangxi are classified by the synoptic method. The weather systems of Guangxi haze days are divided into 8 types: the cold high pressure ridge control, the rear of high pressure moving to the sea, the low pressure trough, the uniform pattern of pressure, the front of cold front, the subtropical high control, the warm area of stationary front, and the peripheral of tropical cyclone. The characteristics of each type and their role in the haze formation in Guangxi are studied. Results indicate that the cold high pressure ridge control, the rear of high pressure moving to the sea, the low pressure trough, and the uniform pattern of pressure types are the four main circulation types which induce more haze days in Guangxi while the warm area of stationary front and the peripheral of tropical cyclone types induce less haze days. The haze processes resulted from the cold high pressure ridge control and the subtropical high control types lasts longer, and those from the front of cold front type have the shortest duration. The small ground wind speed and the sinking airflow at the low and medium altitudes are the common characteristics of all kinds of weather types for haze days.