The purpose of this study was to investigate the effects of neck immobilization with collar orthosis a driving performance. Previous studies have not investigated the effects of neck immobilization on driving performance during the simulation driving. The driving scenario consists of straight and right rotation . The parameters of driving performance included the number of road edge excursions, centerline crossings, and steering angle. Data was analyzed with the Wilcoxon signed-rank test to compare collar group and non-collar group. As a results of simulator driving, steering angle of with-collar group was significantly higher than the without-collar during right rotation. We suggest that neck immobilization has negative effect on driving performance because of substitute motion. We suggest that patients wearing neck collar orthotics should be careful when they drive on road.