Based on available observation data of Zhejiang Province for the period from 1981 to 2013,tem-poral and spatial distribution characteristics of winter haze in Zhejiang Province were analyzed.The results show that haze days have increased significantly since the mid-1980s.Haze days in the northern and west-ern part of the province are much more than the south and the east,also more in the basin and plain than on the hills and islands.The division of the haze distribution pattern is obtained according to the K-means clustering analysis,which shows the pattern can be divided into two categories.The first category ac-counts for 62% of the total haze,most of which happens in December,while most of the second category usually appears in January and December.In the end,according to the NCEP/NCAR reanalysis data,the different atmospheric circulation features,including the strength of cold high,vertical velocity and the dis-tribution of water vapor,are discussed for the two kinds of haze patterns respectively.It is found that Zhe-jiang Province is controlled by cold high from northern China and the sinking airflow in the first haze pat-tern.In the second haze pattern,however,the cold high has transformed,and the sinking flow is also weakened,which makes air move slowly,so it is hard for pollutants to dissipate.%提根据1981—2013年浙江省地面气象观测资料对浙江省冬季霾的时空分布特征进行分析发现，20世纪80年代中期起冬季霾呈显著上升趋势；空间分布总体特征表现为北多南少、西多东少，盆地平原多、丘陵岛屿少。利用 K-均值聚类法将近33年冬季的主要霾过程分为盆地-平原型和全省型两类，其中超过62％的个例表现为盆地平原型，该型以12月发生比例最高；全省型霾过程在12和1月均多发。从气流输送及冷空气强度、垂直运动和干区分布等大气环流背景条件方面对比两类霾过程的形成机理差异发现：盆地-平原型冬季霾多在北方冷空气南下，浙江省受较强冷高压和下沉气流控制时形成，气流来自高纬度；全省型冬季霾则在变性减弱的冷高控制下，下沉气流较弱、不利本地污染源扩散的情况下发生。
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