Abstract: Ocean sound channels play important roles in underwater acoustic signal remote transmission, ranging and positioning, underwater target detection, temperature monitoring, etc. This paper first introduces the concept of ocean sound channel, spatial distributions and characteristics, as well as the key technologies used in ocean sound channel research. Then, the domestic and international progresses in fields such as ocean channel parameter observation, remote acoustic signal transmission, environmental change and fine structure effect, acoustic tomography and climate monitoring, and arctic and full-scale acoustic observation are summarized. Finally, comparing the domestic and international progresses and taking into account domestic demand, the future development directions of China's ocean sound channel research are given.