PURPOSE: To make it possible to accurately detect humidity by a simple temperature compensating means instead of a thermistor through such an arrangement wherein as an element for compensating the temperature of a humidity detecting element, another humidity detecting element of the same kind is used, and this element is covered with heat transfer material for humidity shut off.

CONSTITUTION: One humidity detecting element 1 is coated with epoxy resin under such atmosphere of which relative humidity is less than 20%, and this element 1 is changed in its characteristic so that its electric resistance value is varied only by atmospheric temperature without making response to humidity, and after that, it is connected to the other humidity detecting element 2 in series so that it makes compensation for the temperature of the element 2. Consequently, there is no necessity for separately providing a thermistor for temperature compensation, and by such an arrangement wherein the temperature of one element is compensated by another element having the same temperature-resistance characteristic, humidity can be accurately detected.