Based on the level 1 and relevant ancillary data of the Moderate-resolution Imaging Spectro-radiometer(TERRA/MODIS),the aerosol optical depth over the East China Sea is retrieved by International MODIS/ARIS Processing Package(IMAPP),and the inverse method validated with Aerosol Robtic Network(AERONET) solar direct radiance measurements.The distributive characteristics of aerosol optical depth and ?ngstrm exponent(which symbolizes the width of particle spectrum) over the East China Sea during October—November 2002 are studied,and the backward trajectories analysis of air mass and the background information of geographical environment applied to discussing the applicability of aerosol algorithm and the error source of the aerosol optical parameters retrieved from satellite.The results indicate that the aerosol optical depth obtained by IMAPP over the East China Sea and the open sea area south of Japan are basically in consistent with the result from AERONET.However,the aerosol optical depth is a bit high along the coastal area of Bohai Sea and Yellow Sea due to the influence of Case 2 water.