Provided is an illumination instrument that is for use in endoscopic surgery, and that enables a practitioner during an endoscopic surgery, regardless of the amount of experience of the practitioner, to place the leading end of a light-emitting part at a desired detachment planned site on the back side of an organ, for causing light emitted from the light-emitting part to transmit from the back side to the front side of the organ and for illuminating, in a spot-like manner, "a site indicated by the transmitted light" on the front side of the organ as the "detachment site" on the back side of the organ, so as to enable pinpoint identification of the "detachment site" located on the back side of the organ, from the front side of the organ. This illumination instrument for use in endoscopic surgery is provided with: a grip part having a light source embedded therein； and a light-emitting part that is formed in a long and thin rod-like shape, that has a base end side thereof connected to the grip part and the leading end serving as a contact part which comes into contact with the back side of the organ, and that guides light from the light source so as to emit light, wherein the light emitted from the leading end of the light-emitting part is configured to be capable of transmitting to the front side of the organ.L'invention concerne un instrument d'éclairage qui est destiné à être utilisé en chirurgie endoscopique, et qui permet à un praticien pendant une chirurgie endoscopique, indépendamment de la quantité d'expérience du praticien, de placer l'extrémité avant d'une partie électroluminescente au niveau d'un site planifié de détachement souhaité sur le côté arrière d'un organe, pour provoquer la transmission de la lumière émise par la partie électroluminescente depuis le côté arrière vers le côté avant de l'organe et pour l'éclairage, à la manière d'un spot, "d'un site indiqué par la lumière transmise" sur le côté avant de l'organe comme "site de détachement" sur le c
