An apparatus for transmitting a pilot and method thereof are disclosed, by which a pilot can be efficiently transmitted in a wireless communication system. The present invention, in which the resource unit is transmitted by a base station in a wireless communication system, includes forming the resource unit including a plurality of pilot resource elements (REs) and a plurality of data resource elements, allocating a plurality of pilot pairs to have a prescribed subcarrier interval and a prescribed OFDM (orthogonal frequency division multiplexing) symbol interval within the resource unit, and transmitting the resource unit to a user equipment via multi-antenna, wherein each of a plurality of the pilot pairs includes individual pilots for two different streams or antennas.