The invention provides a traveling auxiliary device and method which are applied to a vehicle. The traveling auxiliary device comprises a recognition module used for recognizing a warning object in front of the vehicle and a position relationship between the warning object and the vehicle, an application module used for determining warning information corresponding to the warning object and generating a projection image according to the warning information, a processing module used for determining the projection position of the projection image in a projection region and the sensing distance between an image formed by projecting the projection image into the projection region and an observer in the vehicle according to the position relationship between the warning object and the vehicle, and a projection module used for projecting the warning information according to the determined projection position and the sensing distance. By the adoption of the scheme, the projection image of the warning information can be displayed near the position of the warning object, so that the warning information and the actual environment are combined, and a driver can obtain information more visually.