First,the applicationvalues,measurement fundamentals and process of the irradiance based method wereexpounded,when it was used in observation of atmospheric environment(OAE).Second,basedon the experiment study by using the VF921-256 spectrometer,some character isticparameters,such as aerosol spectral optical deepth,ozone column content,diffuse-to-global irradiance ratio and aerosol size distribution were retrieved,which arenecessary to OAE. Finally,some error sources which should be considered in OAE werediscussed.