Abstract: In this paper, a scheme of underwater acoustic digital high-speed transmission for towed arrays is proposed. We analyze and build the underwater digital high-speed transmission topology that suits towed arrays, and introduce the system design of transmission node. Additionally, we design control logic of HOTLink Transmitter/Receiver on FPGA and test the bit error rate (BER) of transmission node. The low BER and comparison with ATM node show that the transmission node is feasible. It is an easy way to realize miniaturization of the towed array system.