The invention discloses a paper cutting device for digital printing and capable of directly stacking. The paper cutting device comprises a fixed bottom plate, a roll paper tube, a motor, fan blades and a cutter, a side baffle is fixed to the edge of the fixed bottom plate, the outer side of a guide roller is sleeved with a conveyor belt, and a limiting plate is fixed on the side baffle at the sideof the guide roller; and a fixed plate is fixed to the upper portion of a guide plate, a stacking plate is fixedly arranged at the edge of the side baffle, the motor is installed on the upper end face of a fixed top plate through bolts, the fan blades are fixedly installed at the bottom of a motor shaft, and the motor shaft is connected with a movable cylinder through a belt wheel mechanism. According to the paper cutting device for digital printing and capable of directly stacking, printing paper is automatically cut, the stability of the paper can be guaranteed in the cutting process, the situation that the cutting flatness is affected due to skewing and sliding is avoided, meanwhile, automatic stacking of the paper can be achieved after cutting, the cutting efficiency is improved, andthe working intensity is relieved.