To enable the response speed and the sensitivity to be adjusted even after sealing a package base part with a cap.

In a thermal type infrared-ray sensor in which a sensor element (1) having a light-receiving surface for receiving light of infrared-ray at its one surface is subject to air tight sealing within a package, the thickness from the mounting surface of a mounting part (2a) on which the sensor element (1) is mounted to the outer surface is made to be 200 μm or less. Even after the completion of the packaging, the response speed and the sensitivity can be adjusted by attaching a heat conducting member (9) on the outer surface of the mounting part (2a). In other words, in the case in which the light input is so large that the thermal saturation occurs through the use of an infrared-ray sensor which does not attach the heat conducting member (9), the heat conducting member (9) is attached on the outer surface of the mounting part (2a), thereby making it possible to discharge heat and to avoid the state of thermal saturation. Accordingly, the need can be reduced that the packages must be differently designed in accordance with the respective response speed and the sensitivity.