An infrared image sensor encompasses (a) a base body, (b) a plurality of signal lines disposed on the base body, (c) a plurality of address lines intersecting the signal lines, (d) a plurality of detector portions provided in the cross region of the signal lines and the address lines, each of the detector portions being connected between the corresponding signal line and the address line, each of the detector portions is configured to detect infrared-ray, (e) a plurality of supporting beams supporting each of the detector portions above the base body, and (f) a plurality of contactors configured to contact each of the detector portions with the base body thermally so as to transport thermal energy to be accumulated in each of the detector portions toward the base body.