A prediction model for evaluating permanent deformation in flexible pavements is pre-(sented.) The model is a compromise between simple and advanced approaches,which considers shear factors.In this model uniaxial penetration shear strength is used to evaluate the anti-deformation capacity of asphalt mixture.Shear stress is used to evaluate the anti-rutting characteristics of structure.Based on sub-layer concept the prediction model is established by wheel tests with different temperature,pressure and layer thickness.Finally,the model is verified using wheel test of different asphalt mixtures.The results show that the model can correctly simulate the deformation law of asphalt concrete,and this method also provides the foundation for setting up correct rutting prediction method.