Ligation device and clip unit used therein

Each of the clip units 13 includes a clip body 35 having a pair of arm parts 41 that can ligate the biological tissue and a fastening ring 37 that accommodates the clip body 35, and the plurality of clip units 13 are disposed in series within the distal end of the outer sheath member 19. Each of the fastening rings 37 includes a connecting mechanism 85 consisted by a locking member 87 that connects the adjacent fastening rings 37 each other and a fitting support 101, the manipulation wire 23 engaged with the locking member 87 is pulled to release the connection of the fastening rings 37 by the connecting mechanism 87.