The invention relates to a shaft sealing device with magnetic fluids, which is characterized in that based on an existing shaft sealing device with magnetic fluids mainly comprising a rotating shaft, a non-magnetic metal shell, magnetic poles, a permanent magnet, the magnetic fluids and a rubber ring, sealing pole teeth made of soft magnetic materials are additionally arranged in sealing pole tooth grooves of the magnetic poles, a sealing pole tooth ring is sleeved on the rotating shaft, the inner diameter of the sealing pole tooth ring is 0.1-0.6mm larger than the diameter of the rotating shaft, the outer diameter of the sealing pole tooth ring is 0.1-0.3mm smaller than the inner diameter of each tooth groove, the thickness of the sealing pole tooth ring is 0.1-0.3mm smaller than the width of each tooth groove, the magnetic fluids are distributed in an annular sealing gap between the rotating shaft and the sealing pole tooth ring, and each magnetic pole comprises two half annular magnetic poles. The positions of the sealing pole teeth of the device can be changed radially along the rotating shaft to adjust coaxiality of the rotating shaft and the sealing pole teeth, uneven distribution of the annular sealing gap in the circumferential direction of the rotating shaft is decreased, reduction of the pressure bearing capacity of the device and abrasion of the rotating shaft and the sealing pole teeth are avoided, and the requirements of sealing components on machining and mounting precision are lowered.