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On the basis of the ultraviolet (UV) radiation index and meteorological data from April of 2003 to June of 2006 from Shangqiu, the monthly variation and daily variation of UV index in Shangqiu are analyzed, and the correlation coefficients between UV index and total cloud amount, visibility, temperature and relative humidity are calculated. The results show that: (1) the maximum UV index was in July and August, and the minimum was in January and February; (2) the daily variation of UV index followed the normal istribution, and the strongest period was from 11:00 to 14:00, in which the UV index was higher than 6; (3) the UV index showed good correlation with total cloud amount, visibility, temperature and relative humidity.