In　this　paper,　a　cubic　self-balancing　robot　is　designed.　Taking　a　prototype　of　a　cubic　robot　that　has　been　designed　as　a　specific　research　object.　For　the　attitude　control　of　this　institution.　Using　Lagrangian　Method　to　establish　a　mathematical　model　of　cubic　robot.　For　its　attitude　control　method.　Fuzzy　PID　control　method　was　proposed.　Establishing　simulation　models　in　Matlab/Simulink　environment.　The　simulation　experiments　using　conventional　PID　control　and　fuzzy　PID　control　were　performed　for　comparison.　The　results　show　that　the　adoption　of　fuzzy　PID　control　has　faster　response　speed　and　smaller　overshoot　than　traditional　PID　control　and　has　better　control　effect.