The heart movement affects the body surface electrocardiogram (ECG) and magnetocardiography (MCG). However, in the previous MCG simulation studies, the heart was always assumed static and the heart movement was seldom taken into account. In this paper, we present a simulation study of MCG based on an electrodynamic heart model to investigate the effect of heart movement on MCG. The electrodynamic biventricular model was constructed based on an electrical heart model by a weak electric-mechanic coupling. From the electrodynamic heart model, the deformation of the heart and the relationship of the dipole source and the cardiac electromagnetic field were obtained. The different performance of the MCG and ECG caused by the effects of heart movement and volume conductor model were investigated and compared. The simulation results demonstrated that the including of the heart movement will improve the accuracy of both the simulated ECG and MCG, especially for the ST interval, and the effect of heart movement on MCG is lager than that of on ECG. The volume conductor, however, has larger effect on simulated ECG/MCG of the static heart model based than that of the dynamic heart model based. This study suggested that the heart movement is more important for MCG than ECG, and should be considered in future MCG simulation study.