The invention provides a hardening preventing device for the production of ultraviolet light curing offset printing ink. The device comprises a printing ink box, the printing ink box is movably clamped on a sliding base, and the bottom end of the sliding base is fixedly provided with a mounting base; a driving shaft of a servo motor is provided with a turntable, the turntable is located at the lower end of the printing ink box, the turntable and the right end surface of the printing ink box are both fixedly provided with movable shafts, the movable shafts are both movably sleeved with sleeve shafts, and the two sleeve shafts are fixedly connected through a connecting rod. When the hardening preventing device works, printing ink is put into the printing ink box, the printing ink box can slide on a sliding frame, the turntable is driven by the servo motor to rotate, the eccentrically-arranged movable shafts can drive the connecting rod to move up and down, and the upper end of the connecting rod is also connected with the printing ink box through the movable shafts; through the structures of the movable shafts and the sleeve shafts, it can be ensured that the printing ink box can only slide forth and back in the sliding frame, rolling balls in the sleeve shafts slide more stably, it is ensured that the printing ink is in a flowing state, and the situation is avoided that early hardening of the printing ink is caused by the precipitation of solid impurities in the printing ink.