In this study, the authors first propose a sequence with the impulse-like autocorrelation property named zero autocorrelation code (ZAC) for orthogonal frequency division multiplexing (OFDM) based on offset quadrature amplitude modulation (OQAM) systems. The ZAC sequence can be generated by many prototype filters such as physical layer for dynamic spectrum access and cognitive radio and isotropic orthogonal transform algorithm filters. Thus, it has a wide application range. The authors then propose a synchronisation algorithm based on the ZAC. The proposed algorithm only needs two symbols to compose the preamble while existing algorithms need at least four symbols. They further assess the synchronisation performances via computer simulation. The simulation results show that the proposed algorithm can achieve better performance in terms of root mean square error of the timing and frequency offset estimation, with a 10 dB improvement on timing offset estimation performance over Saeedi-Sourck's algorithm when signal-to-noise ratio is 0 dB.