In this paper, we propose a visual assistance system that shows the scene behind a vehicle to its driver in the form of a virtual mirror by utilizing a surveillance camera. The virtual mirror will be displayed on a windshield display as if it were floating in the air in front of the vehicle. The driver entering an intersection can confirm the safety around the vehicle by checking the image in the virtual mirror while facing forward, because it shows the image of the scene behind the vehicle in an optically correct manner. We utilize a surveillance camera set up on a signal pole. The image in the virtual mirror was formed by applying geometric its transformation to the image taken by the camera so that it satisfy the optical constraints of a mirror.