Disclosed is a distributed antenna system (DAS). The DAS includes a DAS controller, which is an OpenFlow controller, and one or more DAS units in order to dynamically control a traffic transmission policy of the DAS units using an OpenFlow protocol, wherein the DAS controller generates and changes a traffic transmission policy by reflecting a traffic transmission policy change request by operator manipulation or a software-defined network supporting application and a need for changing of the traffic transmission policy according to a status of the DAS unit and a status of a port, and the DAS unit transmits received traffic to a destination according to the policy.