A staple removing device includes an aligning part with which a fold of a booklet stitched by a staple having a crown portion and leg portions and folded along an extension direction of the crown portion is brought into contact, a guide part that guides the fold of the booklet to the aligning part; and a removing part having an operating part that moves in a direction intersecting with the fold of the booklet, to engage with the crown portion of the staple that stitches the booklet.