To provide an automatic palletizer capable of reliably realizing the high speed of a loader.

The automatic palletizer 1 is constituted so that a loader 3 transfers a product in the horizontal X-axis direction orthogonal to the product conveying direction, the Y-axis direction parallel to the product conveying direction, and the vertical Z-axis direction orthogonal to the product conveying direction. The loader 3 comprises: a stand 6; a traverse rail 7 stretched over the stand 6; an electric servo motor 11 for driving the traverse rail 7 in the X-axis direction; a main carrier 16 mounted on the traverse rail 7; a linear motor 17 for driving the main carrier 16 in the Y-axis direction; a vertical post 19 mounted on the main carrier 16; an electric servo motor 22 for driving the post in the Z-axis direction; and a holding means 5 mounted on a lower end of the post 19 to hold the product. In other words, only the main carrier 16 is driven by the linear motor 17.