This paper presents the design of a small off-axis meter-scattering lidar atmospheric detection system to address the issues of large volume and complex structure associated with traditional atmospheric detection lidar. Firstly, the self-built small-scale meter-scattering lidar experimental system was used to carry out 24-hour continuous atmospheric detection in Changchun, and the variation of the contour of the extinction coefficient of atmospheric aerosols is consistent with the actual local situation, which proved that the experimental system was feasible. Secondly, the various factors affecting the accuracy of aerosol inversion are discussed, and appropriate methods are used to remove background noise to improve the inversion accuracy, and it is found that the backscatter extinction logarithmic ratio k and boundary value σm increase with the increase of its value within a certain range, and the lidar ratio Sa is inversely proportional to the atmospheric aerosol extinction coefficient value within a certain value range. Finally, the modification of the system overlapping factor is introduced to enhance the inversion accuracy of near-ground aerosols.