The invention provides a punching machine which can reliably separate punched sheets into products and punching wastes. Movable guiding elements 21 are moved in vertical direction by a guide drive units 22 between a retreating position and a protruding position. The setting section 29 is provided for setting a contact start point on the sheet and a contact end point on the sheet S. The movable guides 21 are moved between the retreating position and the protruding position so as to keep contacting with an area of the sheet S from the contact start point to the contact end point while the sheet S is conveyed from the first conveying unit 15 to the second conveying unit 16.A control part can make themovable guides 21 fall down from the retreating position to the protruding position, so that the movable guides contact with set contact starting positions, so as to start themovable guides to contact with the sheet S. after that, the control part makes the movable guides 21 contact with the sheet S rise from the protruding position to the retreating position, so that the movable guides 21 leave set contact ending positions, and the contact is ended.