Abstract: A knife drive for spreading and thrusting ink through printing matrices of silk-screen printing machines includes first drive members adapted to impart on knives parallel reciprocating movements to a related matrix and comprising at least one plate element reciprocable parallel to the matrix itself, a through-going slot formed in the plate element and parallel to the matrix, and a pin through-penetrating slidingly and rotatably the through-going slot and engaging the knives, and second drive members adapted to impart on the knives up and down movements with respect to the matrix and comprising a guide rigid with the plate element, extending in a transverse plane to the pin and along a transverse direction to the through-going slot, and a small lever attached transversely to the pin and engaging slidingly with the guide.