To compute an exact direction of movement without incorrect detection, even when an action of a pedestrian is very small.

A device 110 for computing the direction of movement computes whether or not the pedestrian is walking, and in which direction the pedestrian moves, backward-and-forward or right-and-left, when he is walking, by using a detection value of an acceleration sensor 120 which detects acceleration in each of backward-and-forward, right-and-left and up-and-down directions of the pedestrian 100. Moreover, the device specifies the state of movement of the pedestrian with high accuracy, since it specifies also the form of the movement of the pedestrian by using the detection value of the acceleration sensor.