To provide a surface plate unit capable of positioning a glass substrate to be subjected to heating by a metal positioning pin with respect to a ceramic surface plate by a configuration which can be manufactured readily and inexpensively.

A surface plate unit includes: a ceramic surface plate 3 on which a glass substrate 2 to be subjected to heating is placed; a plurality of loose holes 4 aligned in positions where the glass substrate is positioned to the surface plate, and penetrated in upper and lower directions; a plurality of metal positioning pins 5 loosely inserted into the loose holes; and a coupling member 6 for coupling the positioning pins to one another on the surface plate to maintain a state where the positioning pins are projected upward the surface plate from the loose holes.