Abstract: A method of receiving downlink data in a wireless communication system according to an embodiment of the present invention includes: receiving a first parameter, for determining the effectiveness of a channel state information-reference signal (CSI-RS) from a special cell, from a first cell; and obtaining information on a sub frame having non-effective CSI-RS by using the number of sub frames to which the paging message of a second cell is transmitted for a reference time, and the first parameter may be different from a second parameter that is transmitted by the second cell and indicates the number of sub frames to which the paging message of the second cell is transmitted for the reference time.