A multi-stage centrifugal compressor includes: a rotor including a plurality of impellers disposed in a plurality of stages in an axial direction; a plurality of diaphragms each including a guide flow path that guides a fluid discharged radially outward from one of the impellers to an adjacent impeller on the following stage, and a communication hole extended from a bottom portion of the guide flow path; a casing that accommodates the plurality of diaphragms therein; and an axial flow path that connects the plurality of communication holes to each other. The casing includes a drain flow path disposed only between the communication hole that is the closest to a suction nozzle and the communication hole that is the closest to an ejection nozzle.