Fuzzy　control　can　deal　effectively　with　many　control　problems　where　precise　mathematical　models　are　difficult　to　be　obtained.　The　fuzzy　control　rules　describe　approximately　the　relation　between　input　and　output　of　controller.　Therefore,　fuzzy　control　has　two　shortcomings　in　the　process　of　controlling　some　practical　complex　systems.　By　deeply　analyzing　the　essential　relation　among　three　input　variables　of　the　three-dimensional　fuzzy　controller,　the　paper　uses　universal　combinatorial　operation　model,　the　combinatorial　connective　of　Universal　Logic,　to　describe　the　logic　relationship.　As　a　result,　a　three-dimensional　composed　variable　based　on　flexible　logic　is　proposed.　And　based　on　the　thought　of　flexible　logic　control　method,　this　paper　put　forward　a　new　type　of　flexible　logic　control　method　based　on　the　proposed　three-dimensional　composed　variable　to　realize　the　effective　control　for　complex　system.　Finally,　the　simulation　experimental　result　of　the　quadruple　inverted-pendulum　system　has　proved　the　correctness　and　effectiveness　of　the　control　method.