Abstract: A program code loading method of an application is applied to a computing system that stores a program code of an application in a flash memory. The program code is loaded in a recording mode, including generating an initial address and a data length of a second program code of the application by executing a first program code of the application. According to the initial address and data length, the second program code is loaded from the flash memory to a DRAM. A replay file, including the initial address and the data length of the second program code, is generated and stored to the flash memory. The program code is loaded in a replay mode, including loading the second program code from the flash memory to the DRAM according to the initial address and data length of the second program code in the replay file.