Abstract: In order to meet the demand for the construction of the passenger ticketing and reservation system of the Boten - Vientiane South section of the China - Laos railway (referred to as the China - Laos railway) and improve its availability and stability, this paper designed a disaster tolerance data synchronization system for the China-Laos railway. Combined with the idea of hierarchical service design, the paper described the architecture and functions of the system in detail, and focused on data disaster tolerance and application disaster tolerance, as well as key technologies such as data compression, message governance, and automatic switching. The system solves the problems such as high code dependency in the dual write operation between database and cache, low data synchronization efficiency and slow failure recovery in the highly concurrent environment, and provides a stable and reliable solution for the data cache synchronization of China - Laos railway.