To solve a problem in a conventional variable light distribution head lamp that a head lamp does not cope with a present curved road under various circumstances since the head lamp is only turned to a turning direction corresponding to an action amount of a steering device.

The variable light distribution head lamp 1 is provided with a main lamp part 4 turned corresponding to a turning of a vehicle and moving a main axis of light distribution from a center line of the vehicle to a turning direction of the vehicle; and a sub-light distribution formation part 7 receiving at least one part of the light distribution at the time of movement from the main lamp part 4 and forming a sub-light distribution directed to an outer side in the turning direction of the light distribution moved from the main lamp part 4. Therefore, since the sub-light distribution forming part 7 in which an irradiation direction and a light distribution shape are made appropriate in order to irradiate a curved road is provided and an optical amount from the main lamp part 4 is distributed accompanying with an operation amount of a steering device, a corresponding ability to the present curved road is enhanced to solve a problem.