To provide a plate-discharging device capable of surely directing the leading edge of stencil original paper to a discharging passage side and effectively preventing a plate-discharging error from occurring.

In a stencil printing device including a printing drum 1, a clamp plate 2 for stencil original paper S and a plate-discharging means 3, a plate-discharging guide 10 is installed which is disposed from the upper position of the leading edge of the original stencil paper opened from the clamp plate toward the plate-discharging means. The plate-discharging guide allows both edges of the leading end of the original stencil paper to curl upward in the width direction and prevents the remaining part except for both edges from curling upward. While both of the leading edges of the original stencil paper curl upward, the part except for both edges is pressed and unable to curl upward and the ability to hold a straight line is secured by turning the center of the leading edge toward the plate-discharging direction. Accordingly, the leading edge is surely directed toward the plate-discharging means, and a failure in plate discharging is prevented.