In recent years, with great importance increasingly attached to atmospheric environmental quality, methods of quantitative analysis for the concentration of atmospheric aerosol was receiving more and more attention. The atmospheric aerosol realtime monitoring system was based on Mie scattering analytical technique, taking the advantage of LabVIEW data stream graphical programming to realize the functions of realtime process, dynamic display and historical data saved. This system analyzed the concentration of sampled various size aerosol particle by realtime getting the backscattering light intensity of every aerosol particle, which can reflect the air quality of current environment. This system had advantages of easy operation, friendly interface and abundant information, which can be widely used for atmospheric aerosol analysis area.