A medical treatment device (12) includes a suturing-ligating member (22), a stopper (26), a fixing member (24) and a suturing-ligation releasing member (30). The suturing-ligating member has a distal end portion, that carries out one of suturing and ligation of biological tissue by puncturing. The stopper is provided to be movable forward or backward on the suturing-ligating member, and stoppable by friction on the suturing-ligating member to maintain the biological tissue in a sutured or ligated state by the suturing-ligating member. The fixing member is provided on the distal end side of the suturing-ligating member to fix the distal end side of the suturing-ligating member to the biological tissue. The releasing member is provided on the distal end side of the suturing-ligating member to release the ligation state maintained by frictional stopping between the suturing-ligating member and the stopper by moving the suturing-ligating member to the distal end portion side with respect to the stopper.
