To provide a light-heat control structure in a building having a means for controlling light-heat quantity in the building, by controlling incidence/reflection quantity of the sunlight into the building.

Eaves 1 (called a light shelf) projects to the outdoor side substantially horizontally installed in the frontage direction of a window part in a height directional intermediate position of the window part 5; and are arranged outside the window part 5 of the building R. This light shelf 1 is provided with the means for controlling the light-heat quantity in the building R, by controlling the incidence/reflection quantity of the sunlight into the building R by the temperature or an incident angle of the sunlight.