To provide an automatic pallet exchanging device capable of improving workability in exchanging workpieces in a set-up range.

This automatic pallet exchanging device exchanges pallets P between a prescribed work range 30 and the set-up range 3 by a rotary type pallet exchanging arm 2. In the set-up range 3, a pallet pull-out device 12 is provided to pull the pallet P outward in a normal line direction to a rotary shaft 1 of the arm 2.