In a tissue binding method, a ring-shaped part (15) of a snare wire (10b) is disposed at a position surrounding a binding target site, the tissue at the binding target site is pulled while the ring-shaped part (15) is pressed against the tissue around the binding target site at a plurality of pressing points that are located away from each other in the circumferential direction of the ring-shaped part (15), and, in a state in which the tissue at the binding target site is pulled, the diameter of the ring-shaped part (15) is reduced to bind the tissue, while adjusting the position in the pressing direction at one or more of the pressing points.