The utility model discloses a gas density relay. The watch comprises a casing, a pedestal, a movement, a temperature compensation element, a dial plate and pointers. Wherein the movement is arranged on the base; and is fixedly connected with the base, the temperature compensation element and the dial plate are both arranged in the machine shell. The dial plate is provided with a shading area and apointer rotating area, the pointer rotating area is arranged to be of a hollow structure, the shading area is located at the position, corresponding to the temperature compensation element, of the dial plate, and the shading area is arranged to be of a shading structure to limit light on the side, away from the movement, of the dial plate to irradiate the temperature compensation element throughthe dial plate; and one end of the pointer can rotate in the pointer rotating area. The gas density relay with the structure can prevent the temperature generated by the external light of the gas density relay from influencing the detection performance of the temperature compensation element.