Abstract: This paper takes Landsat-TM remote sensing imagery about Haian county as the research object.It corrects the TM remote sensing image by four atmospheric correction methods such as the dark-object subtracting method（DOS） and the methods based on atmospheric radiant transfer models such as FLAASH,ATCOR2,6S.It is hoped to find the best methods of atmospheric correction,which is evaluated from every all-around part such as the efficiency and the precision.First of all,TM is used to operate radiance calibration which transforms a DN value of one pixel to its reflectance value.Secondly,it inputs the reflectance values to FLAASH module for getting the image which composed with the real earth reflectance values.The ATCOR2 and 6S have the same flow.They all need to know the locations of objects,the type and the parameters of sensor,the atmospheric parameters and aerosol values and so on.At the same time,the DOS method only depends on DN values of the TM data.Finally,it is the importance of the research to validate the four methods.And using the classification precisions of the Maximum Likely Classification method,they are compared with TM original classification image,which is the best atmospheric correction method with the highest total precision and Kappa coefficient.Through the atmospheric corrections on a certain extent,it receives the realized earth reflectivity and improves the accuracy of the reflection values about rice in advancing the accuracy of crops estimating area.The result showed that,both ATCOR2 and the FLAASH atmospheric correction are good,and both have the large scale enhancement to the recognition precision about crops.But ATCOR2 has a very long computation process,also the efficiency is not high,in which many experience patterns.The counting efficiency of FLAASH is high,and the reflection value about rice equals to the experimental true value basically.Moreover it has the very big help to improve the precision of recognizing crops area.Therefore the FLAASH atmosphere adjustment method can achieve the best effect regarding the crops area extraction.Summarizing some standards like calculated efficiency and results,the FLAASH atmospheric correction methods win better impacts.