The measurement was made in 3 periods from May to September of 2000 in Beijing. The measurement species included SO4(2-), NO3-, NO2-, Cl- of aerosol and related gases. The hourly variation of the concentration was presented. It showed that NO3-, NO2-, Cl- of aerosol and HCl, HNO2, HNO3 of gas varied with regularity. The variation of gas SO2 and aerosol SO4(2-) depended on the emission of SO2. The peak time of SO4(2-) was about 2 hours later than SO2.