A method of transmitting a synchronization signal includes generating a sequence P(k) for a synchronization signal from a Zadoff-Chu (ZC) sequence having the odd numbered length N, the sequence P(k) having the even numbered length N−I, mapping the sequence P(k) to subcarriers so that the sequence P(k) is halved with respect to a DC subcarrier, and transmitting the a synchronization signal in the subcarriers. Time/frequency ambiguity caused by a synchronization error can be avoided, and sequence detection errors can be decreased.