information display device and method for a vehicle are provided . the information display device for a vehicle includes : a camera unit that generates and outputs image information on the rear side of the vehicle ; a main processing unit that performs predetermined functions including an image processing function on the image information ; and a sub processing unit that processes the image information and displays the processed image information on a display unit until the main processing unit ends a booting operation , when the image information is output from the camera unit in a state where the main processing unit is performing the booting operation . accordingly , it is possible to guarantee the safety at the time of backing a vehicle up even when the main processing unit is performing the booting operation and to make a driver not wait until the main processing unit ends the booting operation for the purpose of acquiring necessary information .