A laser power-supply device including a power-supply unit including a voltage input unit into which an AC voltage is inputted, a rectifier circuit, and a plurality of sub-switching regulator units, and a light-emitting unit, in which the plurality of sub-switching regulator units is connected in parallel to output of the rectifier circuit, the light-emitting unit includes a plurality of sub-light-emitting units, each of the sub-light-emitting units includes one light-emitting element row, a current is supplied to the one light-emitting element row from each of the plurality of sub-switching regulator units, and each of the sub-switching regulator units includes a switching circuit, a smoothing circuit, a current detection circuit that detects an output current, and a control circuit that controls the switching circuit on the basis of a current command value and the detected output current.