With the escalation of the South China Seadisputes including the Philippines爷arbitration cases andVietnam爷s threats, China has been facing with enormouschallenges in safeguarding the South China Sea rights.Thus, historical rights play an increasingly important part inthe process. This paper discusses the significant role of theSouth China Sea archives in Taiwan during the period ofRepublic of China, and analyzes the distribution and typesof these archives. In addition, the paper uses ACROSS toillustrate the collection and utilization of the South ChinaSea archives, aiming to provide support for the studies ofSouth China Sea historical basis. It is believed thatcollecting, sorting and utilizing archives in Taiwan duringthe period of Republic of China are of great practicalsignificance for China to tackle the current challenges fromthe judicialization of the South China Sea disputes withVietnam and the Philippines.