That, an infrared sensor comprises a substrate, it is formed on a predetermined region on the diaphragm, diaphragm formed on a substrate infrared and the object to be measured emanating from the object to be measured on the sensor infrared sensor which can compensate for the temperature in itself and compensate its temperature method a second sensor, the first and second sensors to form the first sensor, a predetermined region on the diaphragm for sensing infrared rays radiated from the area other than be detected infrared radiation emanating from areas other than the object to be measured is connected to the first sensor protecting the front of the substrate, including a housing, first, second, is attached to the sensor upper housing IR filter that transmits infrared rays, and consists of a reflecting mirror for reflecting the infrared rays radiated by the object to be measured by the first sensor, the temperature of the infrared sensor at the same time the compensation method Sikkim incident infrared rays radiated by the object to be measured to a first sensor of the first, second Incident infrared rays radiated from the area other than the object to be measured in the second sensor and the first and after sensing the infrared rays that are respectively incident on the second sensor, the temperature of the infrared impinging on the region other than the object to be measured from first and second sensors themselves by compensating outputs only components of the temperature measurement object and the circuit configuration can be simple and reduce the manufacturing cost.