Disclosed is a burglar sensor arrangement structure for arranging, with respect to a vehicle interior member (10), a burglar sensor configured to detect an intrusion into a vehicle interior. The burglar sensor arrangement structure comprises an ultrasonic wave generation unit (2) for generating an ultrasonic wave, and a throat portion (18) for radiating the ultrasonic wave generated in the ultrasonic wave generation unit, from a outside opening (18a) thereof into the vehicle interior, wherein the vehicle interior member is formed with a groove (20), and the outside opening of the throat portion is opened at a bottom surface of the groove.