The invention relates to a multifunctional ball valve assembly for a thickened oil thermal production well. The multifunctional ball valve comprises an upper connector of which the upper rend can be connected with an oil pipe connector, a push-pull sleeve of which the upper end is fixedly connected with the lower end of the upper connector, two gear racks symmetrically and fixedly arranged at the lower end of the push-pull sleeve and extending in the axial direction, a ball valve sleeve of which the upper end is sleeved by the push-pull sleeve and capable of sliding up and down relative to the push-pull sleeve, a ball valve core rotatably mounted in the cavity of the ball valve sleeve through two symmetrically and fixedly arranged ball valve rods, and two gears mounted outside the ball valve sleeve and fixedly connected with the two ball valve rods respectively, wherein a lower connector in sealed connection with an anchor is further arranged at the lower end of the ball valve sleeve; the gear racks at the lower end of the push-pull sleeve are meshed with the gears all the time. In the lifting or pressing process of the upper connector, the gear racks drive the gears to rotate, the gears drive the ball valve rods fixedly connected with the gears to rotate together, and the ball valve rods drive the ball valve core to rotate, so that the opening and closing of the ball valve assembly is realized. The multifunctional ball valve assembly can be widely applied to production operation of the thickened oil thermal production well.