A method for optimizing a data-path by a source Base Station (BS) in a mobile communication network includes determining whether a tunnel among new BSs is set up while tracking a data-flow for a Mobile Station (MS), if the tunnel among the new BSs is set up, determining whether there is a bounce-back, if there is at least one bounce-back, transmitting a first message for detecting a root of an arbitrary bounce-back among the at least one bounce-back and setting up a short-cut tunnel to other end of the arbitrary bounce-back, and after transmitting the first message, receiving a second message including bounce-back root information indicating the root of the arbitrary bounce-back from the other end of the arbitrary bounce-back. Other various embodiments including a source BS, a target BS, and a backhaul network are also disclosed.