Atmospheric aerosols have important impacts on human health,the environment and the climate system.Micro Pulse Lidar(MPL) is a new effective tool for detecting atmosphere aerosol horizontal distribution.And the extinction coefficient inversion and error analysis are important aspects of data processing.In order to detect the horizontal distribution of atmospheric aerosol near the ground,slope and Fernald algorithms were both used to invert horizontal MPL data and then the results were compared.The error analysis showed that the error of the slope algorithm and Fernald algorithm were mainly from theoretical model and some assumptions respectively.Though there still some problems exist in those two horizontal extinction coefficient inversions,they can present the spatial and temporal distribution of aerosol particles accurately,and the correlations with the forward-scattering visibility sensor are both high with the value of 95%.Furthermore relatively speaking,Fernald algorithm is more suitable for the inversion of horizontal extinction coefficient.