PROBLEM TO BE SOLVED: To provide a plunger auxiliary tool which is detachably attached to a plunger and is used, which achieves a quick pull-back operation and a subsequent push-out operation of the plunger performed by an operator.SOLUTION: A plunger auxiliary tool is detachably attached to a flange-state plunger button disposed on a base end of a plunger forming a syringe, for performing a pull-back operation of the plunger comprises in an integrated state: an annular ring part into which a finger of an operator is inserted； a contact part which contacts a rear face of the plunger button； and a pair of plunger engagement parts which are disposed on a front face side of the plunger button, and face each other with an interval so that the plunger is disposed therebetween. The plunger engagement parts comprise in an integrated state, a rotation stop part which engages with the plunger for inhibiting relative rotation when an operator inserts his/her finger into the ring part for performing the pull-back operation of the plunger.SELECTED DRAWING: Figure 1
