Abstract C language programming is more and more favoured by the majority of technical personnel in embedded systems. The application of C language technology in computer software programming can effectively avoid unnecessary language logic problems, ensure the smooth progress of programming work and effectively improve the quality and efficiency of programming. For the development of C language embedded system, the programming ideas of system software are explained, the functional module division based on hierarchical design is given, and the realization methods of project organization, program framework design, module reuse design, etc. in the software development process are clarified. To solve the contradiction between C language flexibility and application development engineering. Although it is introduced for the ARM platform, the basic experience and algorithms are also suitable for software design on other embedded platforms.