PURPOSE: To provide an automatic nailing machine capable of driving nails in a desired arrangement, decreasing working man-hours, and improving the quality of the construction.

CONSTITUTION: The automatic nailing machine 1 is characterized such that a plurality of nails are driven in rows from the surface side of a floor board (object) 3, and there is provided a pressurizer (pressing means) 6 for pressing down the floor board 3 from the surface side, and a nailing machine (driving means) 7 for retaining respective nails and driving these nails on the floor board 3, wherein two nailing parts 4,5 having the compression machine 6 and nailing machine 7 attached thereto are connected in series. Besides, these nailing parts 4, 5 are displaceably supported along the surface of the floor surface 3 by the support body 2 of the automatic nailing machine 1.