PURPOSE: To position and hold a holder means for a base means at a high speed and with high precision, with the simple constitution.

CONSTITUTION: A holder means 13 on which a prescribed positioning objective body is placed asd a part or the whele 13A and 13B of a base means 11 on which the holder means 13 is placed are made of the magnetic material, and a rolling means 12 made of the magnetic material is nipped between the base means 11 and the holder means 13, and the holder means 13 can be positioned through the shift at high speed and with high precision for the base means 11. Further, if necessary, a magnetic attractive force is generated between the holder means 13 and the base means 11 through the rolling means 12 by an electromagnetic means, and the position of the holder means 13 which is positioning-performed can be held with high precision.