The invention discloses a roller coil splitting device and a roller coil splitting and pressing all-in-one machine. The splitting device comprises a splitting machine body; a roller shaft capable of mounting a roller coil is arranged at the upper end of the splitting machine body; a splitting stop rod capable of separating a coil on the roller coil from adhesive tape is arranged at the front end in the splitting machine body; a space capable of enabling the adhesive tape to pass through but not enabling the coil to pass through is formed between the splitting stop rod and the lower bottom surface in the splitting machine body; the roller coil falls down after passing through the space; a hanging tooth capable of hanging the falling coil is arranged on the splitting machine body at the lower end of the splitting stop rod; and the all-in-one machine comprises the splitting device and a pressing machine arranged at the bottom of the splitting device. The splitting device adopts machinery to automatically split the coil, so that the working efficiency is improved, and the cost is saved.