Based on the analysis to the basis data of asphalt concrete pavement of expressways in Hunan Province,and the deficiency of the evaluation method for the damage condition of asphalt concrete pavements,a four indexes evaluation model including rut depth,cracking ratio,pit slot ratio and repair ratio is proposed by triangle whiten function gray clustering method.The new method is adopted to Linchang Expressway maintenance project and the feasibility of the evaluation model has been verified.