Abstract: The paper analyzes the real time performance of Linux2.6 kernel, because the key restrict factors which are clock, critical section and process scheduling, a new method called high-resolution timer is designed and implemented, spin-lock twin module-control method for critical section be adopted, and modify the 0(1) scheduling algorithm, all which are in order to improve the real-time performance of the Linux system efficiently. The test result indicates the improvements are successful to inprove the real-time performance of the Linux system, and the application range in embeded field is expanded.