An ultra-wide head-up display system and a display method thereof are provided. An ultra-wide image displayed by the ultra-wide head up display system is divided into independent head-up display images, an information type of each of the head-up display images is dynamically switched according to a usage status of a vehicle, each of the head-up display images is displayed in a corresponding outer frame, and each of the outer frames is formed by a display region not displaying an image.