On the basis of the meteorological observation data in Hubei Province from 1981 to 2013,the characteristics of spatial-temporal variations of smog and climate elements were analyzed according to the five different judging standards. The results of the analysis indicated that the year around 2000 was a division point of the number of days when smog happened: before the point smog -day number fluctuated with a narrow range,after the point the smog -day number increased significantly,and reached the peak values in 2007. The frequency of smog occurrence was highest in winter,followed by autumn,spring. Generally speaking,smog-day number was in a rising trend with climate tendency coefficient over 0.6 and wavelet transformation indicated that short cycle in five years after 2000 appeared frequently due to the anthropogenic effect. Geographically,the regions where smog frequently occured were Danjiangkou and Xiangyang in northwestern Hubei; Dangyang and Yidu in southwestern Hubei;and Daye in the southeast of Hubei. In addition,the correlation analysis based on the five judging standards suggested the first standard was more suited for the analysis of smog -day in Hubei;and according to the analysis of climate elements,the numbers of smog -day was proportional to temperature,but inversely proportional to relatively humidity,correlation coefficients being about 0.6.