Cultivated land classification and dynamic survey were made respectively for five small towns of Changshu,Jiangsu Province in terms of the method of judging between man and computer for the SPOT data of 1994 and 1999.Precision was analyzed by comparing investigation results with aerial photo survey for 1994.Through a comparison between the area from SPOT image of 1999 with that from aerial photo survey of 1994,we have got dynamic changes in land area for class A type with decreasing rate of 18.3‰ during five years for the five towns.Results show that SPOT image is applicable to survey of county level land use,especially when good phase is chosen and effect of small object on land is redressed.