A method for transmitting user equipment specific reference signals, UE-RSs, for multiple layers, by an eNode B in a wireless communication system, the method comprising: generating reference signal, RS, sequences for resource elements, UE-RS REs, allocated for UE-RS transmission; generating the UE-RSs for the multiple layers by applying different Walsh codes for each of the multiple layers to the RS sequences in the UE-RS REs according to a first Walsh code mapping pattern and a second Walsh code mapping pattern; and transmitting, to a user equipment, the UE-RSs for the multiple layers via the respective multiple layers on a plurality of resource block, RB, pairs allocated to the user equipment, wherein each of the plurality of RB pairs includes 14 OFDM symbols in a time domain and 12 subcarriers in a frequency domain, characterized in that, according to the first Walsh code mapping pattern, elements of each Walsh code are sequentially one-to-one mapped to UE-RS REs of a first UE-RS subcarrier allocated for the UE-RS transmission on a first RB pair among the plurality of RB pairs in a direction of a time domain, sequentially one-to-one mapped to UE-RS REs of a second UE-RS subcarrier of the first RB pair in an opposite direction of the time domain, and sequentially one-to-one mapped to UE-RS REs of a third UE-RS subcarrier of the first RB pair in the direction of the time domain, wherein, according to the second Walsh code mapping pattern, elements of each Walsh code are sequentially one-to-one mapped to UE-RS REs of a first UE-RS subcarrier of a second RB pair among the plurality of RB pairs in the opposite direction of the time domain, sequentially one-to-one mapped to UE-RS REs of a second UE-RS subcarrier of the second RB pair in the direction of the time domain, and sequentially one-to-one mapped to UE-RS REs of a third UE-RS subcarrier of the second RB pair in the opposite direction of the time domain, and wherein the second RB pair is contiguous to the first RB pair in the frequency domain. generating reference signal, RS, sequences for resource elements, UE-RS REs, allocated for UE-RS transmission; generating the UE-RSs for the multiple layers by applying different Walsh codes for each of the multiple layers to the RS sequences in the UE-RS REs according to a first Walsh code mapping pattern and a second Walsh code mapping pattern; and transmitting, to a user equipment, the UE-RSs for the multiple layers via the respective multiple layers on a plurality of resource block, RB, pairs allocated to the user equipment, wherein each of the plurality of RB pairs includes 14 OFDM symbols in a time domain and 12 subcarriers in a frequency domain, characterized in that, according to the first Walsh code mapping pattern, elements of each Walsh code are sequentially one-to-one mapped to UE-RS REs of a first UE-RS subcarrier allocated for the UE-RS transmission on a first RB pair among the plurality of RB pairs in a direction of a time domain, sequentially one-to-one mapped to UE-RS REs of a second UE-RS subcarrier of the first RB pair in an opposite direction of the time domain, and sequentially one-to-one mapped to UE-RS REs of a third UE-RS subcarrier of the first RB pair in the direction of the time domain, wherein, according to the second Walsh code mapping pattern, elements of each Walsh code are sequentially one-to-one mapped to UE-RS REs of a first UE-RS subcarrier of a second RB pair among the plurality of RB pairs in the opposite direction of the time domain, sequentially one-to-one mapped to UE-RS REs of a second UE-RS subcarrier of the second RB pair in the direction of the time domain, and sequentially one-to-one mapped to UE-RS REs of a third UE-RS subcarrier of the second RB pair in the opposite direction of the time domain, and wherein the second RB pair is contiguous to the first RB pair in the frequency domain.