This application provides a synchronization signal transmission method and a communications apparatus. The synchronization signal transmission method and the communications apparatus are applied to the communications field. In the synchronization signal transmission method, a synchronization signal generated and sent by a network device may include a first sequence and a second sequence. The first sequence is a first complex sequence or a sequence obtained based on the first complex sequence. The second sequence is a sequence obtained based on the first complex sequence, and the second sequence is different from the first sequence. Because a correlation processing result between the first sequence and the second sequence is still a complex sequence, there is a good correlation property, so that a terminal device can obtain a relatively sharp correlation peak when synchronizing with the network device based on the synchronization signal, thereby effectively shortening duration required for synchronization.