PURPOSE: To transport a mobile element smoothly using a simple structure by mounting supporting table on both sides of a running path swingably, swinging the table, pressing a pressure roller installed at the supporting table to the side face of the mobile element, and thereby moving it along the running path.

CONSTITUTION: A dolly 1 as a mobile element is placed on a pair of rails 4, left and right, through a plurality of wheels 3 and runs along a certain path 5. A mobile element transport device is arranged at part of this path 5. This mobile element transport device consists of frame 11A at both ends of a base plate 10 passing below the rails 4, while situated at both sides of the path 5, and at each frame 11A a supporting table 15A is mounted by a vertical shaft 13A swingably. A pressure roller 23A rotated by a servo motor 19A through a speed reduction gear 21A is arranged on each supporting table 15A in such a way as rotatable round the vertical axis, and this supporting table 15A is swung through the action of a cylinder device 27A.