To realize a direction detection sensor that can be mounted easily and can detect or judge the direction of an object to be measured from a remote location even in the case of a traveling object to be measured such as a human body, and a direction judgment equipment.

The direction detection sensor 2 that is fitted to a listener H as a hair band emits light signals La... that are modulated with different frequencies from light-emitting diodes 22a... that are arranged so that each light axis becomes radial. In this case, when the direction of the listener H changes, the light-emitting diodes 22a... closest to direction judgment equipment 4 also change, so that the output of each of the light signals La... at the direction judgment equipment 4 changes according to the direction of the listener H. On the other hand, the direction judgment equipment 4 receives each of the light signals La..., detect each output, and compares each output, thus judging the direction of the listener H.