<p>An ultra compact mobility is focused in the view of improvement of transfer for near-distance travel for one to two passengers. This mobility is compact and easy to turnaround, so it can be able to enter narrow roads and bad roads that are not paved. In such a road surface environment, it is susceptible to the influence of vibration caused by steps and unevenness of the road surface, and deterioration of the ride comfort of the vehicle is expected even at low speed running. The authors have analyzed organoleptic evaluation and biological information to improve the ride comfort based on it proposed a control method. In this paper, the stress state of the occupant received by the vertical vibration is clarified from the cerebral blood flow used as an indicator of the activity of the central nervous system. However, each subject varies in biological information. Therefore, multiple regression analysis was performed and the relationship with subjective evaluation by questionnaire was confirmed using biological information of the subject.</p>