A wire harness manufacturing system including a plurality of processing zones and configured to manufacture a wire harness by using a subassembly including a plurality of electrical lines to each of which a connection component is attached includes a conveyance device provided along the plurality of processing zones and including: work boards in a number at least corresponding to the number of the plurality of processing zones; a circulation conveyer configured to sequentially convey each work board in a horizontal state from an upstream side to a downstream side on a downstream conveyance path along the plurality of processing zones and then return the work board from the downstream side to the upstream side on an upstream conveyance path; and a raiser configured to set the work board to a stand-up state in which one of edge parts extending in a conveyance direction of the work board is positioned on an upper side of the other edge part in the work board, and to set the work board in the stand-up state to the horizontal state.