To provide an apparatus for holding a positioning part by which the positioning part can be held without requiring a large area for installing the apparatus, and to provide a method of positioning a workpiece by using the apparatus.

The apparatus 10 for holding a positioning part includes: a link mechanism having a first link 2 fixed on a base M and a second link 3 connected to the first link with a spherical joint 5; a sliding body 7 that is installed in the link body 41 of a third link 4 at the tip end of this link mechanism and that is capable of linearly reciprocating relative to the link body 41; a positioning pin 1 provided at the tip end of the sliding body 7; locking means 8, 8 for locking the turn of the spherical joints 5, 6; and a locking means 9 for locking the sliding of the sliding body 7. In the apparatus 10, the link mechanism and the sliding body 7 operate by following up the movement of the positioning pin 1.