The invention discloses a processing method of a centrifugal compressor clapboard. The processing method of the centrifugal compressor clapboard comprises the steps of fixedly combining an upper sideplate and an upper blade disk, fixedly combining a lower side plate and a lower blade disk, and accomplishing the assembling of an upper clapboard and a lower clapboard; finish-machining center parting surfaces, excircles and end surfaces of the upper clapboard and the lower clapboard; aligning the excircles and planes of the end surfaces of the upper clapboard and the lower clapboard; fixedly connecting the upper clapboard and the lower clapboard on the center parting surfaces, and accomplishing the assembling of the whole clapboard; finish-machining the whole clapboard, and enabling an innercircle, an excircle and the end surface of the whole clapboard to meet the dimensional requirement of a drawing; disassembling the upper clapboard and the lower clapboard, trimming flashing and burrsof the upper clapboard and the lower clapboard; and derusting the upper clapboard and the lower clapboard, so that the processing of the centrifugal compressor clapboard is accomplished. The invention realizes the practical and high-efficiency processing method of the centrifugal compressor clapboard, and fills the technical blank of a current centrifugal compressor clapboard.