To provide a compact stacker capable of stacking and storing storage objects without reversing the obverse-reverse.

A stacker includes a bottom plate 2e, a storage part capable of storing a plurality of cards Cd in a state of stacking on the bottom plate, and a guiding part arranged above the bottom plate and guiding the cards entering from an external part to the storage part. The guiding part has a sidewall 2a for regulating entrance of the card by abutting on the forefront Cdnt of the card when the card enters in the first moving direction DR1 into a stacker 2 in a substantially horizontal attitude, and an inclining part 2h for inclining so that the other Cdml side becomes low by supporting an under surface on any one Cdmr side of the right and left to the first moving direction DR1 of the card in a state of regulating the entrance of the card. The card inclined in the inclining part is guided to the storage part by moving by gravity in the second moving direction substantially orthogonal to the first moving direction, and is stacked on the bottom plate.