Abstract: Firstly, the pressure distribution of the squeeze film isderived via the basic Reynold's equation. Then, the nonlinearcharacteristics of the squeeze-film damper are analyzed by using thetwo-coefficient method. Theoretical analyses and numerical resultsshow that its stiffness coefficients and damping coefficientsare nonlinear with respect to the position, and it is an element of high nonlinearity.So, if the nonlinear fluid film forces are linearized by using thetwo-coefficient method, the caused errors are very great.