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To control the problems of weeds which are frequently and massively occurring under permanent raised bed (PRB) system in Hexi Corridor, a sprayer-and-cultivator-combined multifunctional weeder was designed with the compound configurations of chemical sprayer and mechanical cultivator which were set up on a three-section foldable frame and could be applied alternatively or mutually as to the specific requirement. Three pieces of foldable shields were installed to reduce the drift of the chemicals. As most of the weeds are perennial in the area and can hardly be eliminated by chemical spraying, and also some annual weeds can not be simply cut off by mechanical cultivator, this sprayer-cultivator-combined weeder could function as a manner of integrated weed control along the whole growing period of wheat and maize. Field experiments show that the chemical and mechanical combined treatment managed a significantly better weed-control performance (97.3%) which was higher than either spraying treatment (94.6%) or cultivating treatment (89.2%). That means under permanent raised bed system chemical sprayer and mechanical cultivator combined mode is the optimum pattern to get effective weeds control. 