Abstract: The trend analysis provides an improvement in finding satellite abnormities by using parameter limiting approach, and it helps the satellite in-orbit managers keep abreast of the performance of the key parts of the satellites, as well as possible abnormities. The trend analysis is carried out by focusing on telemetry parameters, and its results help the satellite in-orbit managers improve their abilities in handling problems. With the development of satellite in-orbit management techniques, the trend analysis finds more and more applications in this research area.