To make a curtain install in a driver's seat of a truck and a passenger car to simply realize the adjustment of such a cabin temperature as 'keeping the head cool and the feet warm' favorable to a driver, thereby securing safety driving in a comfortable manner.

This is a curtain consisting of a woven fabric or nonwoven fabric, and it covers the front or a top supplying opening of a first panel 1 of an airconditioner 2 in a cabin, and the girth from the upper knee of a driver and an occupant seat from a front panel mounting part at a position halving a foot supplying opening, and its length is oneleading to a seat back mounting part, and there is another curtain nearly containing with each door inside at both sides of a car body, and this curtain is provided with at least mounting fittings for the front panel mounting part and the seat back mounting part.