Provided is an infrared sensor which is lightweight, is capable of being stably installed, of detecting with high accuracy the temperatures of sections that are separated from a circuit substrate, and of being easily attached. An infrared sensor provided with: an insulating film (2); a first heat sensitive element (3A) and a second heat sensitive element (3B) disposed on one surface of the insulating film (2) so as to be separate from one another; a first conductive wiring film (4A) formed on one surface of the insulating film (2) and connected to the first heat sensitive element (3A); a second conductive wiring film (4B) connected to the second heat sensitive element (3B); an infrared reflection film (6) disposed on the other surface of the insulating film (2) so as to face the second heat sensitive element (3B); a plurality of terminal electrodes (7A, 7B) formed on one end of the insulating film and capable of being inserted into an external connector; an end reinforcing plate (11) adhered to the one end on the one surface of the insulating film; and an attachment hole (2b) formed on the other end of the insulating film.
