To provide an article stacker and an article stacking method for improving recovery working efficiency with a capability of making a plurality of articles collectively taken up on a recovery-work conveying surface.

The articles supplied o a belt conveying surface for placement thereon are conveyed by an endless belt 1 from a supply position to a recovery position. Air pressure is applied to the supplied articles placed on a movable table 2 located on the belt conveying surface at the end thereof, so that the articles are supplied to the belt conveying surface. Then, the belt conveyer surface is moved in fixed displacement to the recovery position by a distance shorter than an article length aligned on a conveying direction. Furthermore, a given number of articles are sequentially supplied and the movement of the conveying surface in fixed displacement is repeatedly executed. This causes the articles to be partially polymerized in placement so that the adjacent articles are partially polymerized with each other so that polymerized article groups are moved to the recovery position and gathered up in a stacking state for collectively recovering capability.