PURPOSE: To provide a position regulating device by which positioning accuracy can be easily obtained by a position regulating rocking arm.

CONSTITUTION: A position regulating rocking arm 2 to be used as a position regulating part by bringing the one rocking end thereof into pressedly contact with a work 3 is provided. On the other rocking end, an elastic body 4 (not shown) for turning the rocking end toward the work 3 is provided. A turnable engaging member 5 by which the projected length up to the end of the position regulating rocking arm 2 can be set in a plurality of steps so as to suit the size of the work 3 is provided. Also a correcting means which is extended in the direction connecting the turning support shaft 2A of the position regulating rocking arm 2 and the turning support shaft 5A of the engaging member 5 and which has a reciprocatable driving means 9 on its end in the extended direction is provided. The turning support shaft 2A of the position regulating rocking arm 2 together with the engaging member 5 is set by the drive of the driving means 9 in the position respondent to the variation of the size of the work 3.