The invention relates to a dividing-cutting machine with a replaceable bottom. The dividing-cutting machine comprises a stander, a total unwinding shaft, a separation roll, a bottom paper winding shaft, a press-fit roll, a lower knife roll, a bottom paper unwinding shaft and a total winding shaft, wherein the separation roll is used for separating bottom paper, and the bottom paper winding shaft is used for winding bottom paper; and the total unwinding shaft, the separation roll, the bottom paper winding shaft, the press-fit roll, the lower knife roll, the bottom paper unwinding shaft and the total winding shaft are located on the stander, the total unwinding shaft and the total winding shaft are respectively located on two sides of the separation roll, the bottom paper winding shaft is located on one side, relative to the total unwinding shaft, of the separation roll and is higher than the separation roll, the press-fit roll and the lower knife roll are sequentially located between the separation roll and the total winding shaft, and the bottom paper unwinding shaft is located above the total winding shaft.