A laser processing system includes a laser processing head, a powder supply device, and a controller. The powder supply device supplies powder to the laser processing head. The laser processing head includes: a laser emission unit which irradiates a workpiece with laser light; and a powder supply unit which receives the powder supplied from a powder supply device to the laser processing head, and can supply the powder to a laser spot on the workpiece. The powder supply unit includes: a powder discharge unit which can discharge the powder toward the laser spot on the workpiece; and a powder-supply control mechanism which controls the amount of the powder to be supplied to the powder discharge unit, by distributing to the powder discharge unit at least a part of a flow of the powder supplied from the powder supply device. The controller controls the distributing by the powder-supply control mechanism.