This paper discusses an assistance system that add tiny torque to the steering wheel momentarily to help the driver choose the direction for avoiding collision with a pedestrian. In order to investigate the effectiveness of the system, we conducted an experiment with a medium fidelity driving simulator. The results of the experiment showed that there existed situations where the system was effective to enhance driver's appropriate selection of steering direction. In addition, the system reduced the driver reaction time significantly. However, there were cases in which the drivers completely disagreed with the system's proposal. In order to make such a system be acceptable to drivers, drivers' way of choosing a direction should be taken into account.