Traditional Chinese acupuncture has a history of over 2500 years. It is effective in the treatment of many conditions with few side effects. The best known mechanism is via endogenous opiates and their receptors. In addition to opioids, researchers have focused on the role of central monoamimergic systems. Acupuncture therapy is used not only to relieve pain but also to treat various medical conditions in traditional Chinese medicine (TCM). Some experiments have revealed a relationship between acupuncture and the autonomic nervous system (ANS). Besides, electroacupuncture (EA) can modulate the imbalance between innate and acquired immune systems. This review is focusing on the mechanistic studies of acupuncture that my colleagues and I have performed in Taiwan in recent years. We found that EA analgesia was closely related to not only the serotonergic neurons but also the adrenergic neurons in the central nervous system. The electrophysiological recordings suggested the involvement of the cerebral cortex in acupuncture. Local somatothermal stimulation inhibited the motility of sphincter of Oddi and internal anal sphincter through nitrergic neural release of nitric oxide. Mild local heat stress upregulated hepatic gene expression of heat shock protein 70 and protected the liver from subsequent ischemia-reperfusion injury. These studies supplement the knowledge of the mechanism of acupuncture.