The invention discloses a large 
barrel polishing and derusting device, and belongs to the technical field of 
polishing and derusting equipment. The large 
barrel polishing and derusting device comprises a worktable, an anti-deviation mechanism, a polishing and derusting mechanism, a dust accumulation mechanism and a rotating mechanism, wherein the anti-deviation mechanism is arranged below the rotating mechanism, the polishing and derusting mechanism comprises a lifting plate, a material shifting 
assembly and a polishing and derusting 
assembly, the material shifting 
assembly comprises two material shifting parts which are the same in structure, each of the two material shifting parts comprises a feeding piece and a lifting piece, the lifting plate is fixed at the top of the two lifting pieces. According to the device, automatic collection operation of generated 
scrap iron can be completed through the dust accumulation mechanism, polishing and derusting operations can be automatically carried out on large barrels with different diameters by the polishing and derusting mechanism, the anti-deviation mechanism can carry out limiting operation on the large 
barrel body, so that large vibration or deviation of the large barrel body during the polishing process is avoided.