A navigation apparatus, including a map data acquiring means 11a, 11, 12, and 5 for acquiring map data including car pool lane data, a current position determining means 13, 14, 15, and 10 for determining a current position, and a display unit 2 for generating and displaying a map of an area in a neighborhood of the determined current position on the basis of the acquired map data, is provided with a road information receiving means 16 for receiving road information in real time from outside the apparatus, a control unit 10 for, when the road information received by the road information receiving means shows that a traffic congestion has occurred in a highway in a traveling direction, judging whether a car pool lane is also provided in the highway on the basis of the map data acquired by the map data acquiring means, and an output means 2 and 4 for outputting a message showing whether or not there exists a car pool lane according to the result of the judgment by the control unit.