Heart diseases, e.g. sudden death, caused by the dysfunction of sino-atrial node could be treated by implanting electronic pacemakers, which, yet, have many disadvantages, such as the limited life of battery and infections. As a result, bio-pacemakers are expected to replace the electronic devices. In the paper, firstly, the inward-rectifier K⁺ current (I_K1) of the ventricular myocytes is inhibited to make the sing cell show automatic pacemaker activity. And then, based on the data of a human ventricular slice, we create a 2D tissue model of bio-pacemaker to investigate the feasibility of inducing bio-pacemaker in the right ventricle. Based on the model, the effects of electrical coupling and the funny current I_f on the pacemaker are discussed. We find that the pacing capability could be increased by both the weak coupling and strong I_f. However, the weak electrical coupling plays a more important role in the bio-pacemaker.