To improve safety during operation in the case that a display unit showing an image during traveling is mounted.

The on-vehicle display unit is provided with a display means 5 for displaying characters and images on a screen, a traveling detection means 6 for detecting that a vehicle is running, and a control means 8 for performing attention display so as not to closely observe the screen on the screen of the display means 5. Even when a map and the like are displayed on the display screen, the attention display meets one's eyes whenever the screen is observed since the attention display is performed on the screen so as not to closely observe the screen, a driver does not observe it closely or the number of times in which he or she observes it closely is decreased, and the power of attention for driving can be enhanced.