In this paper,the dynamic behaviors of the rod fastening rotor which is supported by the fixed-tilting pad gaslubricated bearings are studied. In modeling of the rod fastening rotor,the contact effect of the disks is taken as resistance bending springs with nonlinearity. Based on the boundary conditions of fixed-tilting pad gas-lubricated bearing,the differential transformation method is adopted to solve Reynolds equation,and the gas film force is obtained under the coordinate systerm of the single pad. The gas film force of the fixed-tilting pad gas-lubricated bearing is obtained by coordinate transformation and assembly method. The comparison of stability is implemented between cylindrical gas-lubricated bearing and fixed-tilting pad gaslubricated bearing,rod fastening rotor and integral rotor. Finally,taking the stiffness of the shaft as the control parameter,dynamic characteristic of rod fastening rotor is studied by improved Newmark method. At the same time,the influence of the preloads and pivot ratios on the dynamic behaviors of the system is also studied.