In order to accurately extract the profile image of the ground moving targets(GMT) in the forward scatter radar(FSR),a forward scatter signal model of GMT is built based on the Fresnel-Kirchhoff diffraction formula,the multipath propagation model and the high order phase approximation method.The classical shadow inverse synthetic aperture radar(SISAR) imaging algorithm is modified using the proposed signal model.In the modified imaging algorithm,the impacts of ground reflection,non-linear variation of target Doppler frequency and the target motion direction on imaging accuracy are discussed.Meanwhile,non-linear and time-dependent parameters are used to compensate for the motion phase of the GMT forward scatter signal,and a novel estimation method of the height difference and median line height of the target profile is put forward under the multipath interference.Finally,both the accuracy of the proposed signal model and the effectiveness of the modified imaging algorithm are validated by the simulation results. In order to accurately extract the profile image of the ground moving targets (GMT) in the forward scatter radar (FSR), a forward scatter signal model of GMT is built on the Fresnel-Kirchhoff diffraction formula, the multipath propagation model and the high order phase approximation method. The classical shadow inverse synthetic aperture radar (SISAR) imaging algorithm is modified using the proposed signal model. the modified imaging algorithm, the impacts of ground reflection, non-linear variation of target Doppler frequency and the target motion direction on imaging accuracy are discussed. Non-linear and time-dependent parameters are used to compensate for the motion phase of the GMT forward scatter signal, and a novel estimation method of the height difference and median line height of the target profile is put forward under the multipath interference. Finally, both the accuracy of the proposed signal model and the effectiveness of the modified imaging algorithm are validated by the simulation results.