A suture-fixing system includes an endoscope, a sheath, a suture-fixing tool, a lead-in tool, an engaging portion, a suturing instrument, and an operating portion. The engaging portion is capable of forming an encircled area extended in a loop shape or a U-shape. The encircled area can pass through the suturing instrument. The suturing instrument is capable of having the first delivery member and the second delivery member protrude from the endoscopic channel. The operating portion moves the first delivery member from a position in which the first delivery member and the second delivery are closed to a position passing through the encircled area while the first delivery member and the second delivery member protrude from the endoscopic channel and the encircled area portion protrudes from the distal end of the endoscope.
