The dynamics of 2DOF spherical inverted pendulum system is analyzed. The motion of the pendulum may be projected onto the orthogonal planes in the Cartesian Space. In this way the system can be decoupled into two classical cart-pendulum systems and the design of controllers aimed at each subsystem separately are proposed. The linear quadratic optimal control strategy is applied in order to balance the pendulum system at the ’inverted’ status. The method proposed is verified by the simulation and actual system experiments and the performance of the controller is discussed. The dynamics of 2D pendulum may be projected onto the orthogonal planes in the Cartesian Space. In this way the system can be decoupled into two classical cart-pendulum systems and the design of controllers aimed at at The subsystem separately are control. The linear quadratic optimal control strategy is applied in order to balance the pendulum system at the ’inverted’ status. The method proposed is verified by the simulation and actual system experiments and the performance of the controller is discussed.