To provide a navigation apparatus that dispenses with wiring in a vehicle to detect the operation of a traffic indicator by detecting blinker sound, and enables a user to mount the apparatus easily.

The navigation apparatus comprises a detection means for detecting the blinker sound of the traffic indicator; a current position detection means for detecting a current position; and a determination means for determining the ON/OFF of the operation of the traffic indicator based on detection by the detection means to determine a turning direction based on detection by the current position detection means.