In this paper, we propose a new index inspired by dynamic manipulability for redundent robot proposed by Yoshikawa to estimate dynamic ability to change configuration by using remaining redundancy, while prior task is controlled, for example, end-effectors being controlled to a desired trajectory in task space. Several indexes have been proposed so far to measure statical and dynamical capability of robot manipulator. For example, Dynamic Manipulability Ellipsoid (DME) describes a distribution of hand acceleration produced by normalized joint torque. Besides, Reconfiguration Manipulability Ellipsoid (RME) denotes a distribution of each link velocity produced by joint angular velocity. In this paper, we proposed a new concept named Dynamic Reconfiguration Manipulability (DRM) which combined dynamic manipulability with reconfiguration manipulability, and we examined and analyzed it through simulations to test and verify its validity and usefulness.