The research results of the current supercavitation projectile launching technology are difficult to support the engineering application. Therefore underwater gun launching technology is discussed. This paper summarizes the underwater launching technology of torpedoes and missiles at home and abroad. By introducing the classification of underwater gun automata, concluding the key technologies of underwater gun launching and summarizing the numerical calculation and experimental research results of supercavitation projectile weapon system, the research status of underwater gun launching technology is analyzed. Finally, from the aspects of underwater projectile velocity and barrel pressure measurement technology, the research direction of underwater gun launch technology is prospected. This research has certain practical reference value.