Changing a workplane's origin does not move the workplane. Geometry on the workplane does not move, and the workplane origin slides relative to any existing geometry.
To move a workplane's origin,
1. Click Structure and then, in the Workplane group, click More.
2. Click Slide WP Origin under Modify.
3. Select a workplane and set the new position for the workplane's origin:
◦ Click a point on the workplane.
◦ Type a point (relative to the old workplane origin).
Slide WP Origin under Modify.
to complete the operation.