Virtual seat method(VSM) which is an evaluation method combined objective and subjective process is used in this study in order to determine seat comfort index of idle vibration of passenger vehicle. The VSM is implemented by two steps which are for objective index in the first step and for subjective estimation in the second step. In the study, two seats mounted on passenger vehicle was compared in terms of dynamic seat comfort by six subjects employed for the VSM method as well as SEAT value which is a conventional objective method. It is concluded that the dynamic comfort index by the VSM is more reliable than the SEAT value thanks to adding subjective evaluation on top of the objective result.