The measurement error in geomagnetic navigation is a key factor of affecting the accuracy of geomagnetic navigation, and the carrier interferential magnetic field, including eddy current magnetic field, is the main factor of error. At present, a large number of carriers made of ferromagnetic materials inevitably cause eddy magnetic fields and other interferential magnetic fields. Therefore, this paper establishes a simulation model of eddy interferential magnetic field of highspeed moving carrier by adopting COMSOL Multiphysics simulation software. First, the relationship between permanent magnet and uniform magnetic field is studied. It turned out to be that the stronger the remains of permanent magnet, the stronger the uniform magnetic field, which provides a theoretical basis for simulating the geomagnetic field. Secondly, the influence of eddy current magnetic field on geomagnetic measurement is analyzed when the carrier rotates at constant speed. Finally, the distribution of eddy current field is studied when the carrier swings. The results show that the eddy current magnetic field increases with the increase of velocity, and the eddy current magnetic field is mainly located in the middle of the carrier. The simulation results provide a theoretical basis for the error modeling and the magnetic field correction technology in the future geomagnetic navigation.