In order to study the influence of backscattering of indicating laser in laser guidance process and laser guidance countermeasure test, the scattering function and volume extinction coefficient of typical aerosol distribution are calculated, and the backscattering detection model of 1.06 μm horizontally transmitted laser is established, based on Mie scattering theory and scattering function optimization algorithm; the model is used to study the change of backscattering energy detected by the detector at different positions and different detection angles, and the false-alarm area of laser guidance along the indicating laser path under different detection thresholds is obtained. The results can help to deepen the understanding of the influence of atmospheric scattering on the laser guidance process, and provide theoretical reference for the scheme design of the laser guidance countermeasure test.