This paper presents an optimal trajectory planning method of the dual arm manipulator using Dual Arm Manipulability Measure(DAMM).When the manipulator carries an object from a certain position to the destination,various trajectory candidates could be considered.To select the optimal trajectory from the several candidates,energy,time,and the length of the trajectory could be utilized.In order to quantify the carrying efficiency of dual-arms,DAMM has been defined and applied for the decision of the optimal path.DAMM is defined as the intersection of the manipulability ellipsoids of the dual-arms,while the manipulability measure indicates the relationship between the joint velocity and the Cartesian velocity for each arm.The cost function for achieving the optimal path is defined as the summation of the distance to the goal and inverse of this DAMM,which aims to generate the efficient motion to the goal.It is confirmed that the optimal path planning keeps higher manipulability through the short distance path by using computer simulation.To show the effectiveness of this cooperative control algorithm experimentally,a 5-DOF dual-arm robot with distributed controllers for synchronization control has been developed and used for the experiments. This paper presents an optimal trajectory planning method of the dual arm manipulator using Dual Arm Manipulability Measure (DAMM) .When the manipulator carries an object from a certain position to the destination, various trajectory candidates could be considered.To select the optimal trajectory from the several candidates, energy, time, and the length of the trajectory could be utilized.In order to quantify the carrying efficiency of dual-arms, DAMM has been defined and applied for the decision of the optimal path. the manipulability ellipsoids of the dual-arms, while the manipulability measure indicates the relationship between the joint velocity and the Cartesian velocities for each arm. the cost function for achieving the optimal path is defined as the summation of the distance to the goal and inverse of this DAMM, which aims to generate the efficient motion to the goal. It is confirmed that the optimal path planning keeps higher manipulability through the short distance path by using computer simulation. Show the effectiveness of this cooperative control algorithm experimentally, a 5-DOF dual-arm robot with distributed controllers for synchronization control has been developed and used for the experiments.