Abstract: This paper analyzes and studies the magnetic anomaly characteristics of each component of the lithospheric magnetic field in the view of pre-earthquake changes of the lithospheric magnetic field near the epicenter of the Madoi M_S7.4 earthquake using geomagnetic field vector data of the mainland of China in 2020 and 2019. The results show that before the Madoi M_S7.4 earthquake, the lithospheric magnetic field components near the epicenter all changed to varying degrees. The Madoi M_S7.4 earthquake epicenter is located at the weakly magnetic anomaly region, and near the zero-variation line of all the components. The Madoi M_S7.4 earthquake epicenter is located between the high gradient belt and the low gradient belt of all the components. This paper confirms that the lithospheric magnetic anomaly will be changed before the earthquake, and summarizes characteristics of geomagnetic components magnetic anomaly, and provides a case for the future study of the seismo-magnetism, especially the earthquakes that magnitude larger than 7.0.