The atmospheric transparecy under atmospheric background polltion in East China is studied. The resuhs show that the characteristics of change of atmospheric transparecy in three wavelengths is mainly the same. The atmospheric transparecy is lower in May and Sep. and higher in Jan. ,July,Dec. ,and highest in 778nm and, lowest in 368nm. The attenuation function of aerosol particle is biggest in effects. The frequency paragraph idstribution present minor normal.