文章简要论述了嵌入式软件系统的总体结构，分析了系统中各个模块的组成及其作用，并对清华嵌入式操作系统（THOS）内核的构架也作了详细的介绍。关键词：开发板支持包；图形用户接口；嵌入式操作系统内核Abstract: The whole structure of embedded software system is introduced in this article. And then the functions of every module in this system are analyzed. Moreover, the architecture of the kernel of "TsingHua Embedded Operating System"（THOS）are also presented in detail.Key words；BSP（board support package；GUI（graphics user interface)：kernel of embedded operating system