the present invention is an improvement in a staple sheet cartridge for an automatic stapler where sheets of staples are delivered to the forming and driving section of the stapler by a conveyor belt . a retaining protrusion is formed on a guide member such that contact area of , and perpendicular force on the staple sheet are maximized without auxiliary magnetic means , allowing smooth , positive and consistent delivery of the staple sheets to the forming and driving section of the stapler .