A single-use syringe includes a deformable sealing member which is in a fluid-tight and slidable engagement with a barrel wall, a plunger which is disposed to be movable along the barrel wall, a first coupling member which is secured to a front end wall of the plunger, and which has a first connected end disposed forwardly of the front end wall, and a second coupling member which is secured to a trail end wall of the sealing member, and which has a second connected end disposed rearwardly of the trail end wall. The second connected end confronts the first connected end in a radial direction, and is attached to the first connected end at a bonding region. Immediately after the second connected end stays put as a result of abutment of the sealing member against a shoulder of the barrel, a subsequent forward force applied to the plunger breaks the bonding region, thereby preventing operation of the plunger to move the sealing member rearward, and thereby rendering the syringe unreusable.