A transient elastohydrodynamic lubrication (EHL) model for the finite line contact between the roller and the raceway in the cylindrical roller bearing was established.The decay curve of the contact pair under free vibration was obtained numerically by using the chasing method,fast Fourier transform technique and Newmark scheme.Through combining the EHL model with the free vibration model of the damping system,a method for predicting the dynamic parameters of the rollerraceway contact pair was proposed with the mutual approach variation selected as the criterion for measuring the vibration of the contact pair.Effects of the initial disturbance quantity,pressureviscosity coefficient of the lubricant,length of the roller and load on the stiffness and damping coefficients were investigated.Results show that under small perturbation,influences of the initial disturbance quantity on the stiffness and damping coefficients are negligible.The stiffness under EHL condition is smaller than the Hertz stiffness under dry contact,and it is increased with the increasing of lubricant pressureviscosity coefficient,roller lengthtodiameter ratio and load.The damping coefficient under EHL condition is decreased with the increasing of lubricant pressureviscosity coefficient,increased with the increasing of roller lengthtodiameter ratio and decreased with the increasing of load at a certain range.