An analysis is made of the data of solar ultraviolet radiation (UV) observed at Taiyan for three years. The results show that UV is the highest in sunny midday, obvious higher in summer than in winter, and the occurrence time of the highest UV is earlier in summer than in winter. Some meteorological factors and air pollution of the same time is also analyzed, and the results shows that UV is influenced by cloud form, cloud cover, air pressure, air temperature, visibility, humidity, air pollution, etc. The ratio of UV to the global radiation is higher in summer than in winter, and the attenuation is not synchronous in cloudy days. It is suggested that halfhour averaged maximum UV and averaged UV from 10:00 to 14: 00 have the same importance for UV forecasting, so to estimate the possible harm of UV to human bodies.