The invention provides a workbench assembly for a hair planting machine. The workbench assembly comprises a rack; two parallel guide rails are arranged on the rack; the heads of the two guide rails are fixedly connected with the tails of the guide rails; a plurality of processing stations are arranged along the guide rails; the guide rails are in sliding connection with seat bodies in one-to-one correspondence with the processing stations; hairbrush clamping assemblies for clamping hairbrushes are arranged on the seat bodies; two sets of adjusting assemblies are oppositely arranged on each seat body; the two sets of adjusting assemblies are erected on the two guide rails respectively; each adjusting assembly comprises a connecting seat fixedly connected to each seat body and two adjustingpieces arranged on the connecting seat; each adjusting piece comprises an adjusting seat rotationally connected to each connecting seat and two rollers rotationally connected to the two ends of the adjusting seat; and each guide rail is located between the two rollers. The spent time is relatively short when the workbench assembly for the hair planting machine matches with the hair planting machine to perform hair planting, and the hair planting machine does not need to be paused in the process, so that the hair planting efficiency of the hairbrushes is greatly improved.