The present invention relates to the technical field of polishing devices. Provided is an automatic polishing apparatus for a tablet computer. The present invention solves the problems in the art in which a polishing device for a tablet computer housing has a complex structure and operations associated therewith are complex The automatic polishing apparatus comprises a workbench (1), a first adjustment assembly (2), a second adjustment assembly (3), a rotating assembly (4) and a polishing assembly (5). The first adjustment assembly (2), the second adjustment assembly (3) and the rotating assembly (4) are all mounted on the workbench (1). The polishing assembly (5) is mounted on the second adjustment assembly (3), and is positioned above the rotating assembly (4). A housing, of a tablet computer (100), to be polished is placed on the rotating assembly (4). The second adjustment assembly (3) is used to cause the polishing assembly (5) to move left and right. The first adjustment assembly (2) is used to cause the second adjustment assembly (3) and the polishing assembly (5) mounted thereon to move forward and backward. The automatic polishing apparatus can be used to thoroughly polish a housing of a tablet computer and has improved polishing performance. Compared with the prior art apparatuses, the above automatic polishing apparatus has a simple structure, is convenient to operate, does not require manual operations, and can effectively reduce labor intensity.