Abstract: A tag pin attacher has a casing including a space which is defined by a vertical wall and has a protrusion at a central part thereof, two horizontal walls formed perpendicular to the vertical wall, and a horizontal guide formed between the horizontal walls; a tag pin feed mechanism including an elevating plate which is received in the space and slides along the protrusion, the elevating plate having a cam groove, a rocking lever having a pin at a lower part thereof pivotally supported to the elevating plate, and a finger member horizontally interconnected to the rocking lever; an extrusion mechanism including an arm which abuts the rocking lever to turn the rocking lever, a cam member which is engaged with the cam groove of the elevating plate to move the elevating plate up and down, an interconnector having a yoke formed at a forward part thereof, the yoke abutting against the finger member to push the finger member forward, and a slider which is disposed within the interconnector and slides between the hori