To provide a light-emission adjustment device that can adjust a distance between a light-emitting member and a lens and concentrate or diffuse a light source and having a suitable heat radiation effect.

The light-emission adjustment device includes a reflecting cup, and an aluminum plate. The reflecting cup takes on a hollow conic body wherein both ends are opened openings. An opening at one end of the reflecting cup has a lens, a side of the reflecting cup has at least one groove, and a peripheral side of the aluminum base plate has at least one connecting tube which can vertically move up and down in correspondence to the groove. The light-emitting member is arranged on the surface of the aluminum base plate, and the light source of the light-emitting member can be approached to or separated from the lens while the aluminum base plate is adjusted and displacement of the connecting tube is interlocked. Burning of internal members is prevented while concentration or diffusion of the light source is changed and calorific values of the light-emitting member and the reflecting cup are conducted and radiated with the connecting tube.