This invention is directed to reliably condensing weak light by a sensor arranged at a position spaced apart from a processing position. The optical processing head includes a light guide that guides light for irradiating a processing position. The optical processing head further includes a light transmitter that has one end arranged near the distal end of the light guide and the other end connected to a photodetector, condenses reflected light traveling from the processing position, and transmits it to the photodetector. The optical processing head includes at least one light transmitter as its feature.