In this letter, we proposed a simple balanced-detection reception scheme for the half-cycled single-sideband direct-detected optical orthogonal frequency division multiplexing (HSSB DD-OFDM) signal with decreased guard band. By employing this scheme, each entire OFDM symbol can be recovered perfectly, while the signal-to-signal beat interference (SSBI) can be eliminated, the guard band can be reduced greatly and the tolerance to phase noise induced inter-channel interference (PN-ICI) and potential benefit of low peak to average power (PAPR) are retained. The simulation results demonstrate that a 40 Gbps 16-QAM HSSB DD-OFDM signal was achieved successfully.