Abstract: A thumbtack tacker tacking thumbtacks by pushing action comprising a case provided with a arc-shaped housing portion housing a lot of thumbtacks inside the case, an arm provided with a V-shaped pick-up member picking up a thumbtack inside the arc-shaped housing portion along the arc-shaped face of the arc-shaped housing portion at the tip and pivoted inside the case, a working slide provided with a suspended portion engaging the arm and supported as swingable to the back and front of the case with the front end of the arm faced the front of the case, and a reversing plate provided with a magned attracting the thumbtack picked up by the pick-up member, being pivoted as reversible to the front face of the case.