An insect trapping unit (1) that is provided with an adhesive sheet (10) that includes a fluorescent brightening agent (103) and that can transmit ultraviolet rays, and with a reflective member (20) that reflects ultraviolet rays that have been transmitted through the adhesive sheet. The adhesive sheet is provided with an adhesive surface (101) and with a rear surface (102) that is on the opposite side from the adhesive surface. The reflective member faces the rear surface of the adhesive sheet.
