The invention discloses a drying device for material machining. The drying device comprises a case. A first stirring shaft, a second stirring shaft and a third stirring shaft are fixed to an inner cavity of the case; stirring blades are fixed to the outer surfaces of the first stirring shaft, the second stirring shaft and the third stirring shaft correspondingly; a spiral feeding shaft is arrangedin the inner cavity of the case; a first gear is arranged at one end of the spiral feeding shaft; a shaft rod is arranged on the case; a second gear engaged with the first gear is arranged at one endof the shaft rod, and a first bevel gear is arranged at the other end of the shaft rod; a second bevel gear engaged with the first bevel gear is rotationally arranged on the first stirring shaft; a rubber pipe is arranged at a discharging outlet, and a supporting ring is arranged in the rubber pipe; an adjusting mechanism used for adjusting the diameter of the supporting ring is arranged on the case; and a gravity sensor is mounted in the inner cavity of the case and electrically connected with the adjusting mechanism. The spiral feeding shaft is arranged for stirring and conveying materials,so that the materials are fully heated and evenly dried, and meanwhile the discharging speed is increased; and by arranging the supporting ring, the size of the rubber pipe is adjusted, and accordingly the discharging speed is effectively controlled.