Abstract: Traditional backscattering lidar has complex system and requirement to correct the geometrical factor. Using imaging lidar can overcome these drawbacks and this lidar can work all the day. It adopted the weighted fitting method, slope method and modified iteration algorithm that combined Klett backward integration method and Genetic Algorithm(GA) method based on the distribution of extinction to deal with the image data. Taking the data from four different weathers, the atmospheric visibility of these days was obtained. Then, it was made a confrontation with the America Belfort model 6230A visibility meter. It can achieve from this process that the differences of visibility between two facilities were on the small side and had the high correlation coefficients over 0.67. Finally, it can reach a conclusion that this imaging lidar system can be a new instrument to measure the atmospheric visibility.