Abstract: An electronic device includes a memory and a program. The program includes a plurality of sub-modules, wherein each sub-module includes a plurality of stub functions and a plurality of functions, each stub-function corresponding to an address of a function respectively. The method for updating the program includes setting a plurality of stub-function in a first sub-module, and calling a first stub function in advance for getting an address of a first function when calling the first function. In the present invention, the time load of linking and down loading programs when updating programs is substantially reduced.