Disclosed are a support body, a body fluid collection set, and a body fluid collection method that can easily support a body fluid collection sheet even by a non-physician. The support body 1 includes a first sheet 10 having an adhesive surface 12 for adhering the body fluid collection sheet 30, and a second sheet 20 adhered to the first sheet 10. The adhesive surface 12 of the first sheet 10 is adhered to the body fluid collection sheet 30 so that the first sheet 10 is separated from the skin 40 and the body fluid collection sheet 30 is peeled off from the skin 40. Thereafter, the second sheet 20 is superposed on the adhesive surface 12, and the body fluid collection sheet 30 is supported on the support body 1.
