The present invention relates to a method for transmitting and receiving data via a first base station supporting a first radio access technology (RAT) and a second base station supporting a second RAT in a radio access system supporting a multi-radio access technology, and the method may include allowing the first base station to perform a registration procedure with the second base station; and allowing the first base station to transmit control information required for accessing the second base station to a terminal supporting multi-RAT (multi-RAT terminal), wherein the control information comprises beacon frame transmission timing information of the second base station, and the beacon frame transmission timing is maintained in transmission timing of a downlink frame or downlink sub-frame of the first base station with relative timing offset interval.