The utility model relates to a waste disassembling and breaking up device, which comprises a bunker door (7), a electromotor (1), a cantilever support (4), a rotating shaft (10), a flattening board (8), a flattening nail (9), a driving belt wheel (2), a slaving belt wheel (5), and a transmission belt (3), wherein the electromotor (1) is downwardly arranged at the outer side of the bunker door (7), the cantilever support (4) is transversely arranged at the inner side of the bunker door (7), the rotating shaft (10) is vertically arranged at the end of the cantilever support (4), the flattening board (8) is vane-shaped and arranged at the upper end of the rotating shaft (10), the flattening nail (9) is vertically and downwardly connected with the vane terminal of the flattening board (8), the slaving belt wheel (5) is arranged at the lower end of the rotating shaft (10), the driving belt wheel (2) is arranged at the output terminal of the electromotor (1), and the transmission belt (3) is sheathed on the driving belt wheel (2) and the slaving belt wheel (5). The utility model can disassemble baled waste/old paper, newspaper and magazines, and break up the pasteboard and boxes with larger size. The baling materials are uniformly laid in the bunker, and the shaped enclosed block is more compact and has uniformly distributed density.