uC/OS-II is a small, but powerful preemptive embedded real-time operating system, which is mainly characterized by open source code, determined program running time and low requirements of hardware resources. Based on uC/OS-II operating system, the design scheme of spaceflight controller is introduced from three aspects. The first aspect mainly introduces the bottom transplantation strategy of uC/OS-II operating system, which mainly consists of four steps such as the coding of key transplantation files and the coding related to the porting target CPU. The second aspect is the design of board level drive layer. The third aspect introduces the detailed design strategy based on uC/OS-II operating system controller, in which application layer is mainly divided into several tasks, and being processed respectively according to the task priority. Finally, combining with the system requirements, the PC testing system is designed to test the parallel tasks. Experimental results show that the system can be running correctly and the expected function can be realized.