Abstract: The lunar exploration is an important task of Chinese space exploration, and the lunar interior structure exploration is one of the important research directions. Based on transient electromagnetic method, this paper presents the lunar interior structure exploration based on the solar storm. In this exploration method, magnetic field jump generated by solar storms is used as the detection source to generate polarization in the lunar interior. At the moment of the magnetic field transition, the internal medium polarization of the lunar generates an induced magnetic field, and the internal structure information of the lunar can be obtained through the detection and processing of the magnetic field signal. In this paper, the forward simulation of the induced magnetic field signal is carried out, and the simulation experiment can verify the validity of the detection method and the correctness of the forward algorithm, which lays a foundation for the subsequent research.