New characteristics of supercontinuum emission generating along with ultrashort femtosecond laser self-guided propagating in air, such as ultra wide band spectrum and backscattering enhancement, produce a new study field for the development of atmosphere detection lidar. The backscattering properties of supercontinuum emission from a self-guided filament generated by femtosecond laser are researched by measuring the angular distribution of supercontinuum emission at different conditions of air. The results show the backscattering of supercontinuum emission from a filament is enhanced in clear air and dusty air with aerosol. And by fitting the experimental data of the backscattering of supercontinuum emission, it is found that the angular distribution of supercontinuum backscattering satisfy Lorentz function; in clear air the angle width is 6.4°, the normalized backscattering intensity increases 3.2 times as compared with Rayleigh scattering at 180°. Along the filament, the frontward supercontinuum emission exhibits the conical emission, so frontward scattering is obviously dependent on wavelengths; the backward scattering shows no obvious dependence on wavelengths.