A centrifugal compressor bundle that is provided with a bundle main body in which is formed an annular intake flow channel (FC1) that is centered on an axis line (O) and that leads a process gas (G) into a flow channel (FC) of an impeller, and in which is also formed an annular discharge flow channel (FC2) that is centered on the axis line (O) and that discharges the process gas (G) from the flow channel (FC) of the impeller. The bundle main body has a plurality of diaphragms that are aligned in the direction of the axis line (O) and that are bonded to each other. From among the plurality of diaphragms, an intake diaphragm in which the intake flow channel (FC1) is formed is partitioned so as to have an upper-half part and a lower-half part that sandwich, from above and below, a horizontal plane that includes the axis line (O). The upper-half part and the lower-half part have the same rigidity in the direction of the axis line (O).