In an infrared sensor (1) having a bolometer element (11) and a reference element (21), the reference element (21) comprises a bolometer film (22), a substrate-side insulating film (31) formed on the substrate-side surface of the bolometer film (22), a heat dissipation film (23) made of amorphous silicon formed on the substrate-side surface of the bolometer film (22) with the substrate-side insulating film (31) interposed therebetween, and a plurality of heat dissipation columns (25) made of amorphous silicon thermally connected to the heat dissipation film (23) and a substrate (10), while the bolometer film (22) and substrate-side insulating film (31) are formed such as to extend over a side face of the heat dissipation film (23) intersecting a surface of the substrate (10). Thus configured infrared sensor (1) can efficiently reduce the influence of temperature changes in the environment in use, while being made smaller.