In this paper, the timing synchronization is studied and proposed a synchronization acquisition algorithm based on least-squares estimation. The advantages of the poposed algorithm is that it can reach a compromise between complexity and synchronization performance and also obtain good synchronization precision under certain SNR (Signal to Noise Ratio). Takes Time-Hopping Ultra-Wideband Pulse-Amplitude-modulate signal system as an example, simulation results have demonstrated the feasibility of the proposed method and verified the theoretical analysis.