The change of the solar ulrraviolet radiation caused by changes of the factors such as ozone,water vapour and aerosol, was calculated based on the observations of solar spectral radiation in 1990 over Beijing area. The solar uhraviolet radiation will increase 0.84%, 0.27% and 1.90%respectively while ozone, water vapour and aerosol decrease 5%. The influence Of all the factors affecting solar ultraviolet radiation should be considered comprehensively as analysing the variation trends of solar ultraviolet radiation.