A math model of the sinoatrial node (SAN) is presented, based in last experimental results in literature. This model was proposed by H. Zhang, A. V. Holden and M.R. Boyett and was implemented and verified in order to obtain a better understanding of the processes associated with generation and propagation of action potentials into the mammal sinoatrial node. Math models are used to investigate the ionic base that supports the pacemaker activity in central and periphery cells of SAN. This implementation is the support to develop a sensitivity analysis in the model as the next step in the investigation line.