PURPOSE: To provide a tightening prier which is convenient and comfortably usable and has a degree of freedom in design.

CONSTITUTION: A tightening prier includes approximately elongated fixed units 2, 3 having fixed handles 4 formed at one ends and fixed jaws 3 formed at the other ends and movable units 6, 8 having a movable jaws 6 mounted on the fixed jaws via a pivotally supporting pin on the one hand and one ends connected to the movable jaws via a joint and the other ends provided with driving levers 8 forming a movable handle 11 on the other hand. A toggle mechanism 18 connected to the midway of the lever 8 via joint consists of a link 12 adjustable along the length of the fixed handle 4 and extending to a rear bearing point. The driving lever 8 is formed by connecting the joint 7 of the movable jaw 6 to the bearing point 14 of the link 12 and the fixed handle 4 extends almost along a line D2 connecting the joint 9 to the bearing point 14.