PROBLEM TO BE SOLVED: To improve a heat dissipation characteristics while securing a sealing property inside an outer case of a lamp fitting.SOLUTION: A lamp unit is provided with: a light source unit 12 having a light source 51, a reflector 50 and heat sinks 49, 49, ...; a fixed frame 9 fixed inside the outer case of a lamp fitting 4; a movable frame 8 supported by the fixed frame in free movement in an up-and-down direction; a lens unit 7 having a projection lens 14 and a lens holder 13 and supported by the movable frame in free movement in a right-and-left direction; a first aiming operation shaft 10 for adjusting an optical axis by moving the movable frame in an up-and-down direction; and a second aiming operation shaft 11 for adjusting an optical axis by moving the lens unit in a right-and-left direction. The lens unit is displaced to the right-and-left direction and the up-and-down direction against the fixed frame in a state that a distance from a focal point of light reflected by the reflector to the projection lens is made constant, and the light source unit is fixed to a lamp housing in a state that the heat sink is placed outside the outer case of the lamp fitting.