In this paper, we propose a new motion control algorithm of multiple mobile manipulators for handling a single object in cooperation with a human. In general, for handling the object, robots grasp it rigidity and a human operator applies an intentional force/moment to it. However, when the robot is operated by a human who does not have enough knowledge about robots, he/she may apply his/her intentional force/moment to the object without considering the singular configurations of the robot. The singular configuration problem is an indispensable one for the motion control of the robots with many degrees of freedom including humanoid robots and mobile manipulators. In addition, when we utilize multiple mobile manipulators, we have to consider the redundancy of the mobile manipulator and the slippage problem between the wheels of the mobile base and the ground. These problems make the human operator be difficult for handling the object in 3-D space. In this paper, we design a new motion control algorithm of multiple mobile manipulators so that they could handle the object in cooperation with a human without regarded to the several control problems of the mobile manipulators.