The Raman multi-channels lidar developed by Wuhan University is described.The design principles of the whole system and main technical parameters are provided.The methods for retrieving aerosols’ optical properties such as atmospheric aerosol extinction coefficient,backscattering coefficient and lidar ratio are presented in detail,and the key part of retrieving the aerosol extinction coefficient is discussed and analyzed.The real-time detections of optical properties for aerosol,cloud and boundary layer in the low-altitude atmosphere are done.The experiments show that the multi-channels Raman lidar system has good performance for detecting the vertical distribution of aerosols in the night and it is reliable.