In the central nervous system, pituitary adenylate cyclase-activating polypeptide (PACAP) exerts different actions as neurotransmitter, neuromodulator, neurotrophic and neuroprotective factors via multiple signaling pathways. PACAP plays an important protective role in the nervous system diseases, such as focal cerebral ischemia, traumatic brain injury (TBI), schizophrenia, anxiety disorders Parkinson's disease and Alzheimer's disease. Now, we reviewed the research advances about the protective role of PACAP in the nervous system diseases.