Operating room monoreflector light includes a dome or hood-shaped upper housing portion and a lighting means arranged in the upper housing portion, preferably as an LED lighting means, including an LED board on which a plurality of LEDs are arranged. A main reflector is arranged in the upper housing portion and deflects a light flux produced by the lighting means through a light exit opening closed by a cover plate of the upper housing portion. To reduce the necessary installation space and to simplify the construction, the upper housing portion is in one piece and extends interruption-free from an upper end which is directed upwardly in the installation position to a lower end which defines the light exit opening. The upper housing portion includes a fixing plane for the LED board, and on which an LED light module is or can be mounted.