The invention discloses a vertical straightening device. The vertical straightening device comprises an upper row of rolling pressure rollers and a lower row of rolling pressure rollers, the upper row of rolling pressure rollers and the lower row of rolling pressure rollers are arranged alternately, and a die-cutting knife is arranged between the upper row of rolling pressure rollers and the lower row of rolling pressure rollers and is vertically arranged. According to the vertical straightening device, the lengths of the two sides of the produced die-cutting knife are uniform, the phenomenon that products are unqualified due to radians is avoided, the operation is simple, and the work efficiency is improved.