The growing contradiction between the exponential increase in data amount and the limited storage capacity of existing media is becoming increasingly evident, necessitating the development of new types of media to address this issue. Due to its ultra-high density, low energy consumption and long lifetime for data storage, DNA has attracted significant attention as an emerging storage medium, particularly for massive “cold data”, with the potential to replace current storage methods. In the process of data storage, the effective preservation of DNA plays a crucial role, directly impacting the quality of storage density, stability, storage time, as well as data writing and reading. Due to the limited information available on DNA preservation techniques in the current literature, this paper provides an overview of current research progress and strategies in DNA preservation technology for data storage, discusses the difficulties and challenges faced when applying existing preservation techniques in DNA data storage, and presents prospects for the implementation of DNA data storage.