To make an ink hard to fly and prevent or restrain a printing machine or works from being contaminated.

In a printing machine, an ink I is supplied to an ink reservoir 3 to be formed in a valley between an anilox roll 1 and an ink roll 2. An excess ink I is made to overflow from at least one end part of each of the rolls 1 and 2, which is circulated to the ink reservoir 3 through a circulation line 9. An ink fly preventing mechanism 20 comprises an air injection nozzle 21 which is arranged on at least one of the roll 1 and the roll 2 at least near one end part in its axial direction. The air to be injected from the nozzle 21 gives a force in a direction different from a rotating tangent line direction of the roll to the reservoir for the excess ink to be formed at the end part of the roll, so that flying of the excess ink incident to the rotation of the rolls is restrained.