In　this　paper　a　PLC　control　system　is　designed　to　control　the　sorting,　transmission　and　loading/unloading　in　the　manufacturing,　in　view　of　the　defects　of　the　relay　control　system　which　usually　has　poor　reliability　and　bad　flexibility　in　use.　On　the　basis　of　the　superior　performance　of　PLC　control　system　and　the　working　principle　of　frequency　converter,　AC　transducer　drive　technology　is　applied　to　achieve　stable　starting,　reliable　operation　and　low　breakdown　rate　in　the　assembly　line　of　manufacturing.　In　the　design　of　the　upper　monitoring　system,　the　functions　of　parameter　settings,　process　monitoring　and　control,　data　processing,　fault　location　can　be　well　implemented　via　configuration　software.　The　research　work　of　this　paper　will　lay　a　solid　foundation　for　the　design　of　material　automatic　sorting　system　based　on　the　PLC　controller.　©　(2012)　Trans　Tech　Publications,　Switzerland.