In order to meet the urgent requirements of space remote sensing, a spaceborne low-distortion and super-wide-angle aerosol imager system is designed. The system is a multi-spectral imager with the working wavelength band from 0.860 μm to 0.965 μm, and its full field of view is 94° and the relative aperture is 1∶4. By using a retrofocus structure, its back working is 42 mm in the optical system. Based on the aberration characteristics of retrofocus structure, methods for correcting distortion and improving the illuminance distribution are proposed. Its distortion is corrected by choosing suitable quadric surface, and the illuminance distribution on image plane is improved by using effective aberration vignetting resulted from stop aberration. Ray tracing, optimization and analysis are performed by CODE V and ZEMAX software. The analysis results demonstrate that the maximum distortion is less than －1.6%, and the illuminance at edge field of view is higher than that of 46.9% of central field of view and the MTF is higher than 0.59 at Nyquist frequency 38.5 lp/mm, which satisfies the requirement. Its structure is compact and feasible for space remote sensing. The design method is proved to be feasible.