A holding apparatus holds a flexible plate wound on a circumferential surface of a holder of a printing machine. A holding apparatus includes a hole section made in the holder along an axial direction of the holder, a groove section made by notching the circumferential surface of the holder along the axial direction to establish a connection with the hole section and accept insertion of a leading edge end portion and trailing edge end portion of the plate, a tension bar inserted and fitted into the hole section for engaging the trailing edge end portion of the plate, and a rotating mechanism provided in the hole section for rotating the tension bar.