The dynamic properties of tires vary with the running conditions. This fact makes tire vibration analysis of tires difficult. The analytical techniques on both a tire with vehicle weight and a rotating tire are introduced in this paper.First, the constrained modal method is applied and the dynamic characteristics are identified. Then the vibration of the suspension system is simulated and the calculation results are compared with the experimental results.In case of rotating tire, the corrected modal parameters are used. The correct constants are obtained by hammering test and the response of the axle due to a projection or “cleat” is calculated. From the results, we are sure these methods are applicable to the vehicle vibration problems.