Mesolimbic dopaminergic system has been recognized for its central role in motivated behaviors, various types of reward and learning. The recent studies have shown that the reduction of neuronal activity in the nucleus accumbens under the neuropathic pain contributes to pain transmission. It has been also expected that the control of mesolimbic dopaminergic neuronal activity affects adult neurogenesis and control of pain. However, little, if any, is known about multi-physiological actions controlled by mesolimbic dopaminergic neuronal activity. The recent development of optogenetic tools has provided a valuable opportunity to inhibit or stimulate activity in genetically targeted neural populations with high spatial and temporal precision. In this study, we performed the multiplex assay using transgenic mice expressing channelrhodopsin-2 or halorhodopsin protein under the control of the tyrosine hydroxylase promoter. The optogenetic activation of mesolimbic dopaminergic neurons in transgenic mice changed the expression of several genes related to adult neurogenesis in the hippocampus and produced analgesia, whereas it failed to produce hyperlocomotion. On the other hand, the optogenetic suppression of mesolimbic dopaminergic neurons in transgenic mice decreased morphine-induced analgesia. These findings provide evidence that mesolimbic dopaminergic system may play a crucial role in neurogenesis and control of pain.