The invention relates to a large-volume propylene polymerizer. The large-volume propylene polymerizer comprises a motor, a reducer, an upper end socket, an inner drum, a lower end socket and a stirring shaft, and is characterized in that an upper jacket is soldered on the outer wall of the upper half part of the inner drum, and a spiral upper deflector is arranged between the upper jacket and the upper half part of the inner drum so as to form an upper spiral cooling channel; an upper cooling water inlet and an upper cooling water outlet are formed in the outer wall of the upper jacket and are communicated with the upper spiral cooling channel; a lower jacket is soldered on outer walls of the lower half part of the inner drum and the lower end socket, and a spiral lower deflector is arranged among the lower jacket, the lower half part of the inner drum and the lower end socket so as to form a lower spiral cooling channel; and a lower cooling water inlet and a lower cooling water outlet are formed in the outer wall of the lower jacket and are communicated with the lower spiral cooling channel. By reinforcing the stirring and heat-exchanging performance, the stirring effect of the propylene polymerizer is reinforced, the material fluidity is reinforced, and the heat exchange capacity is improved, so that the yield of a single polymerizer and the product quality can be improved.