Abstract: Aiming at the sampling clock synchronization in HF antenna array, a high-precision clock synchronization algorithm is proposed. Based on the analysis of PTP, the accuracy of the time stamp is improved by detecting the rising and falling edges of the clock pulse. Then a clock synchronization circuit is designed based on FPGA, and a simulation platform is built for verification. The simulation results show that the algorithm leads to high-precision synchronous sampling for HF antenna array.