Mirrors are used for showing the backward view in conventional driving. However, it has become possible to present the rear space using cameras and monitors as international regulations have been changed in recent years. This increases the freedom of choosing the type of the backward view. The purpose of this study is to experimentally clarify how human spatial perception is influenced by the display method, especially the presentation position and the viewpoint. We prepared a setup in which a simulated vehicle moves while the participant views the front and backward virtual 3-D space. We analyzed the subjective evaluation, the performance, and the eye movement of participants during the task and searched for an optimum presentation position and viewpoint. As a result, we found that it is easier for participants to understand the space with an integrated monitor rather than separated monitors. They could better unify the viewpoints of the rearview and the side view, objectively or subjectively, when these views are independent. In contrast, we suspect that either viewpoint was suitable when presenting the entire backward view with one camera. Also, we suggest that their ease of understanding the space varies considerably depending on the visible field in the bird’s-eye view.