A light-beam therapeutic apparatus used for a therapy for neonatal hyperbilirubinemia is disclosed, which includes an apparatus body portion having a light source; a light guide rod that guides light from the light source, a connecting socket, a cooling fan, an electronic component that performs control required for a therapy, and a control display panel that displays the contents of therapy; a therapeutic portion including a light guide portion including a plurality of bundled optical fibers, and a pad portion formed of the optical fibers spread out adjacently to one another into a flat-panel shape, and the therapeutic portion is formed into a light-receiving plug insertable into a connecting socket of the apparatus body portion, and the optical fibers positioned on the pad portion are subjected to exposing processing and have a protecting surface layer portion formed of a bag member filled with transparent and highly flexible high-molecular gel.