Abstract: A thermal infrared camera includes a thermal infrared image pickup element with a plurality of light-receiving parts generating heat in response to incident infrared radiation. The incident infrared radiation is detected using changes in electrical characteristics of each of the plurality of light-receiving parts, an image-focusing optical system used for image pickup, and a temperature-controlled infrared radiation blocking body that has an opening for conducting infrared radiation from the image-focusing optical system to the thermal infrared image pickup element. The temperature-controlled infrared radiation blocking body is positioned around the thermal infrared image pickup element. The thermal infrared image pickup element is mounted on a first temperature control means used to control a temperature of the thermal infrared image pickup element.