To provide a display device of sensor equipment suitable for adding a display function to the sensor equipment, while keeping the function of the sensor equipment alive.

This device is equipped with: a lid body used by being replaced with a lid of the sensor equipment, mounted on the sensor equipment body equipped with a sensor element, and covering a relay terminal table for measurement data output by the sensor element integrated in the sensor equipment body; a display such as a liquid crystal display provided on the lid body, for displaying visibly measurement data by the sensor element from the surface side of the lid body; and a plurality of contactors provided on the back face side of the lid body, for electrically connecting the sensor element to the display by abutting respectively on a prescribed terminal on the relay terminal table when the lid body is mounted on the sensor equipment body.