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Using the ultraviolet ray monitoring data from 2006 to 2008 in Shijiazhuang， the characteristics of the ultraviolet radiation in the past three years are analyzed. The results show that the UV levels of Shijiazhuang ranged from Level 1 to Level 4， corresponding to 175， 251， 220， and 432 for the number of days， respectively. The relatively high level occurred most frequently， and the moderate level and higher accounted for 60.3%， which means that Shijiazhuang is an area with relatively highlevel ultraviolet radiation. The ultraviolet radiation was the strongest in spring and summer and the weakest in winter. The diurnal cycle of the ultraviolet radiation was very obvious， with a singlepeak distribution. The main meteorological factors that affect ultraviolet radiation are determined through correlation analysis. The ultraviolet index forecast equation containing a number of weather factors is established by using the multiple regression method. The accuracy rate of the equations for various seasons was above 50%， with the best accuracy rate being over 70% for autumn and winter. The equations could be used in operational ultraviolet index forecasting.