In the present invention, a method for transmitting/receiving data in a wireless access system and a base station for same are disclosed. More particularly, the method comprises the following steps: setting a cell group per at least one cell having an identical uplink-downlink configuration, if a plurality of cells are set to a user equipment; performing via a first cell cross-cell scheduling with regard to a second cell, which belongs to a cell group that is different from that including the first cell, according to the uplink-downlink configuration of the first cell; confirming the occurrence of a collision subframe, in which an uplink subframe and a downlink subframe exist simultaneously in the same time interval, in two cells performing the cross-cell scheduling; and transmitting/receiving data with the user equipment when scheduled in the collision subframe due to the cross-cell scheduling, by modifying a transmission position of the uplink or the downlink according to the cross-cell scheduling.