A leveling apparatus for a vehicle headlamp has a case body, a motor disposed
within
the case body, a worm wheel supported by the case body rotatably but unmovably
in the longitudinal direction and rotated by the motor and a shaft screwed into
the worm wheel. The shaft and the worm wheel are screwed together by thread ridges
provided on the inner side of the worm wheel and thread ridges provided on the
outer periphery of a driven portion forming the shaft. The thread ridges on one
side out of the thread ridges on two sides are formed by one to two pitches.
