Biological pacemaker has attracted more and more attention of the researchers. The aim of this manuscript is to investigate the effect of the electrical coupling at the border on the pacing and driving of the biological pacemaker in ventricle. First of all, a 1D ventricular strand model containing a pacemaker is developed by using the anisotropic reaction diffusion equation. Based on the model, the initial pacing time (IPT), action potentials of the cells in special locations, and the propagation process of the electrical excitation are simulated corresponding to different couplings at the border, and it is found that to an extent, the pacing of the pacemaker is enhanced by weakening the coupling. However, when the coupling is small enough, the excitation of the pacemaker could not effuse, making the driving failed. In addition, the relationship between the minimum size of the pacemaker and the coupling is also probed, which reveals that the smaller the coupling is, the less the pacing cells are required. Nevertheless, the relationship is not prominent. In conclusion, it plays a certain role in the functioning of the pacemaker to reduce the coupling at the border alone. Nevertheless, other measures should also be taken to create an effective biological pacemaker.