Abstract: How to accurately monitor the stress-concentration and fault of high-speed rail caused by temperature stress is an unsolved problem for a long time. The model for the rail and ambient air was constructed with the software of ANSYS based upon finite element analysis(FEA), and was used to analyze the stress-magnetization effect on the rail under the geomagnetic field. The distributions of stress and magnetic flux leakage under different load were given. From the comparative analysis on the simulation results and the experimental ones obtained from the magnetic memory methods, the distribution of magnetic field in the vicinity of the defect by load was given, providing useful information for the mechanism research and application of high-speed rail magnetic flaw detection.