Abstract: Boards to be dried, such as veneer are placed, one after another, on a pair of fork conveyors disposed opposite to each other. The boards are kept in the form of layers separated and carried downwardly in this fashion, so that the boards can be dried by hot air blown and circulated in the horizontal direction through a space between the two conveyors during their downward voyage. The space between the two fork conveyors is divided into a central passage portion and right and left passage portions, and the flow amount of the hot air at the right and left passage portions is controlled to be somewhat less than the hot air at the central passage portion. In this way, possible dry cracking and wave-shaped shrinkage can be effectively prevented.