A headlight controller and a vehicle headlight system including an ADB can include a headlight controller and an optical unit. The headlight controller can include a system controller, a vehicle detector and a camera photographing forward vehicles located in a travelling direction of a subject vehicle, and the system controller can be configured to output a light-emitting control signal to provide favorable light distribution patterns by using vehicle data output from the vehicle detector in accordance with image data output from the camera. The optical unit can be configured to provide the favorable light distribution patterns using lights emitted from a right and left light-emitting device in accordance with the light-emitting control signal. Thus, the disclosed subject matter can include providing vehicle headlight systems that can form various favorable light distribution patterns by utilizing the characteristics of the headlight controller and the optical unit in accordance with various traffic conditions.