Cyclic axial loads generated by the traffic significantly affect the deformation characteristics of the base and subgrade materials, which becomes an important factor for the rutting damage of the pavement structure. On the other hand, for a fixed point in the pavement structure, the direction of stress constantly changes during the movement of the wheel load, defined as principal stress axis rotation (PSAR), which also affects the deformation of the pavement structure. Mechanistic-Empirical Pavement Design Guide (MEPDG) proposed a model that combines resilient and permanent deformations to predict the rut depth of unbound granular materials. However, there are some disputes about whether the effect of PSAR has been considered. This study examined the behavior and relation of the resilient strain and permanent strain of crusher-run gravels under the effect of PSAR by multi-ring shear tests and further verified the validity and reliability of the MEPDG permanent axial deformation predictive model.