A data structure design system for prolonging the life of an FRAM (Ferroelectric Random Access Memory) includes a CPU (Central Processing Unit) (1), an FRAM (2), an SDRAM (Synchronous Dynamic Random Access Memory) (3), and a clock (4). The FRAM is divided into a plurality of fixed-size blocks, and is for storing data. The SDRAM is for storing data that need to be written to the FRAM, and includes three data structures: queue one, queue two, and hash table. The CPU is for reading data from external storages, storing the data in the SDRAM, reading data from the SDRAM, and writing the data to the FRAM via the three data structures. The clock is for recording a predetermined time used to determine the blocks in the FRAM in which data have not been read up to the predetermined time. A related data structure design method is also provided.