An ink container holding device for a rotary printing machine includes: a pack holder detachably receiving an ink container; a support table on which the pack holder is slidably mounted, wherein the pack holder is slidable between a connecting position where an ink discharge port of the ink container is connected to an ink suction port of an ink supplying pump and a disconnecting position where the ink discharge portion is disconnected from the ink suction port; a supporting member on which the support table is secured, the supporting member being movable between a first position inside the printing machine body and a second position outside the printing machine body; a holder set board secured to the printing machine body; and a hook lever connecting to the pack holder, wherein the hook lever moves the pack holder to the connecting position by engaging the hook lever with the holder set board in accordance with the supporting member moving to the first position.