To provide an offset printing machine, which can prevent a small-sized card at its non-marginal printing by a simple constitution from winding round a blanket and consequently an efficient continuous printing is performed.

In an impression cylinder 11, an adsorbing mechanism, in which a sequential suction is started through the connection of the impression cylinder side sucking passage 27 on the rotational directional head side of the impression cylinder 11 with the sucking hole 29 on a pump side and a card K passing through a nip part as being gradually adsorbing onto an adsorbing part 24 from the tip side of the card to its rear end side is carried by a predetermined angle and then the adsorption of the card is released gradually from the tip side of the card to its rear end side for its delivering to a discharging device, is equipped.