A method and an apparatus for mapping a bit of an enhanced physical downlink control channel (e-PDCCH) in a wireless communication system are provided. A base station maps an e-PDCCH bit on a first region to which the e-PDCCH is allocated from a data region within a subframe, and maps a redundant bit of the e-PDCCH bit on a second region, which is between a control region and the first region within the subframe, including at least one orthogonal frequency division multiplexing symbol (OFDM). The e-PDCCH bit is mapped from a kth OFDM symbol within the subframe in the direction of an increasing OFDM symbol index, and the redundant bit is mapped from a (k−1)th OFDM symbol in the direction of a decreasing OFDM symbol index.