Embodiments of the present invention relate to a wireless communication system, and more particularly, to a technology for allocating a Channel State Information-Reference Signal (CSI-RS) in a wireless communication system. Embodiments of the present invention provides an apparatus and method for allocating CSI-RSs to resource areas, in which, under the condition of a subframe in which the CP is an extended CP, and the duplex scheme is TDD, if CSI-RSs for maximum 8 antenna ports are allocated, the CSI-RSs are allocated to the 8th and 9th symbols (symbol No. l=7 and 8), wherein each CSI-RS for every two antenna ports is allocated to the same RE while being discriminated from each other by an orthogonal code and neighbor CSI-RS allocated REs in the frequency axis are spaced by an interval of three REs.