As the real-time embedded systems are more and more complex, the existing RTOS design method, such as hardware and software separation,hardware and software coordination and so on, is unable to meet the requirements of its implementation. Combined with the core idea of MDA and MIC, this paper proposes a method based on model-driven for the RTOS design, which combines the temporal semantics with the Servant / Exe-Flow Model. Firstly, the paper gives the abstract semantics of the meta model expressing SEFM, and describes the concrete syntax of SEFM using XML language and block diagram language. If a different specific syntax can express the same abstract syntax, then each of them can be transformed into the other. Combined with XML parsing technology, the code generation of SEFM can be realized. Finally, the experiments of the following vehicle system show that the method of system design is feasible and correct.