Abstract: For ULF/VLF communication between ship and submarine at more than one hundred kilometers distance, the propagation rules of ULF/VLF waves excited in the symmetrical half-space is analyzed. Further more, based on the ULF/VLF atmosphere noise spectral density, the gain of the transmitting and receiving antennas and the thermal noise from the antennas and receiver, the communication distance, the penetrating depth and the communication rate of the shipborne ULF/VLF submarine communication system is analyzed in detail.