An automatic spacers mounting system includes a horizontal arraying pallet to hold spacers therein in a horizontal direction; a posture changing pallet and a shutter. The posture changing pallet and the shutter are coupled to the horizontal arraying pallet, such that the posture changing pallet faces the horizontal arraying pallet, and are rotated by 180 degrees with the horizontal arraying pallet. An inserting guide having a plurality of guiding holes is positioned above a panel having sprayed glue thereon is placed. The posture changing pallet and the shutter are disposed above the inserting guide, the plurality of spacers are inserted into the plurality of guiding holes, and a plurality of pressing pins of a pressing chuck are inserted in the guiding holes and press the spacers against the panel.