The continuous solid-state polymerisation device of the present invention comprises: a feeder for continuously introducing a prepolymer; a horizontal reactor which is connected via a first connecting part to the feeder and receives the prepolymer from the feeder so as to subject same to solid-state polymerisation, wherein the reactor itself is rotated; a stirring device which comprises a stirring shaft rotating inside the horizontal reactor, in the direction opposite to that of the rotational axis of the horizontal reactor, and comprises stirring blades joined vertically to the stirring shaft; and a chamber which is connected via a second connecting part to the horizontal reactor and, once the solid-state polymerisation has been completed, receives the resulting polymer discharged from the horizontal reactor, and, here, the feeder, the horizontal reactor and the chamber are in a vacuum state. The continuous solid-state polymerisation device prevents the formation of prepolymer stagnation zones, and allows solid-state polymerisation to take place continuously in the vacuum state without any inert gas.