To examine the functional role of hyperpolarization-activated and cyclic nucleotide-gated (HCN) current observed in mesencephalic dopaminergic neurons, we constructed a conductance-based model that can mimic the electrical properties obtained in electrophysiological recordings of rat brain slices. In the model, blocking the HCN current resulted in a reduction of spontaneous firing rate and a change in the properties of autonomous pacemaking. In addition, reduced one-dimensional phase equations and their coupled oscillators were analyzed. The analysis indicated that HCN channels can regulate the extent of synchronization of coupled dopaminergic neurons through gap–junction connections. Thus, the HCN current can effectively shape the autonomous and cooperative firing of dopaminergic neurons in the midbrain. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.