A distribution pattern of the vehicle headlight is transitioned according to a vehicle speed, between three light distribution patterns. The patterns are a normal mode corresponding to a light distribution variable control state, an OFF mode corresponding to a low-beam state, and a residential mode corresponding to a high-beam light distribution that does not give a glare to pedestrians. It is determined whether or not a detected vehicle speed is within a predetermined range that enables transition of the light distribution pattern to the residential mode, and it is determined whether or not an immediately-preceding execution state of the light distribution pattern has been the normal mode. Transition between modes of the light distribution pattern is prohibited when a detected vehicle speed is determined to be within a predetermined range, and the immediately-preceding execution state is determined to have been the normal mode.