Abstract: Using the ground meteorological observation data of Chengdu and its surrounding areas (including Meishan,Guanghan,Mianyang and Deyang) during 1980~2010,based on kinds of statistical methods,the spatial-temporal distribution characteristics of haze days in this region are analyzed in detail.The results show that the annual average haze days in Chengdu and its surrounding have an increasing tendency,especially in last five years.Seasonal average variation of haze days main performe that winter is most,autumn and spring are next,summer is at least,and the haze days in this region are increasing in summer,autumn and winter,but decreasing in spring.A significant difference of monthly average haze days generally shows a“V”word,the maximum haze days occur in December and the minimum in June.The annual average of haze days are consistent,high value areas distribute in the southwest of Chengdu and the eastern Jintang,Guanghan,Deyang,Mianyang,but the low value areas distribute in the north of Chengdu.