Abstract: A fast extraction technology for image object in led tracking system is studied.The image object model of the system is described.The possibility of extraction for image object's characteristic graph is analysed aceording to the defin itions of condensation degree and recognition degree presented.The method to produce the result with maintained character,which is used to extract system's image object is introduced through statistic studies and theoretical analysis for a large number of real images by means of histogram.Finally,some experimental results for real images show that the method in this paper is applicable.