This paper presents the control of an aerial manipulation system with a quadrotor and a 2-DOF robotic arm by using the computed torque control method. The kinematic and dynamic model of the system is obtained by modeling the quadrotor and the robotic arm as a unified system. Then, the equation of motion of the unified system is got in the form of a standard robot dynamics equation. For the trajectory control of the system, computed torque control is used. Gains of the controller are optimized by using nonlinear least squares method. The performance and stability of the control structure are tested with a simulation case study.