Abstract: The development of the nuclear industry is a key part of China’s “the 14^th Five-Year Plan”, and reactor decommissioning is an important part of the construction of advanced nuclear industry system. Cutting and disassembling technology is the key technology in reactor decommissioning and the bottleneck technology in the process of reactor decommissioning. Therefore, the research of cutting technology is of great significance. In this paper, the characteristics and classification of underwater cutting technology and cutting disassembling technology in the nuclear facility decommissioning were summarized. The research status of underwater laser cutting technology, underwater plasma arc cutting technology, underwater disc saw cutting disassembling, diamond wire spacing cutting technology and high pressure water cutting technology in the nuclear facility decommissioning was analyzed. After investigation and analysis, it is concluded that the underwater cold cutting technology has various cutting capabilities, good incision quality, easy operation, cutting process, no pollution to the environment, no risk of fire, and has more advantages than the underwater hot cutting technology. Therefore, the underwater cold cutting technology is suitable for the cutting and disassembling of medium and strong radioactive pipelines in the nuclear facility decommissioning. In addition, in the air, diamond wire spacing cutting technology and high pressure water cutting technology are widely used, and have their own cutting advantages. Finally, based on the background of Heavy Water Research Reactor, this paper puts forward the further development direction of cutting technology.