Hydrocephalus is a common primary or secondary central nervous system disease? which often leads to poor quality of life or even disability and death. It is a great challenge for neurosurgery because of its complicated etiolo gy, unclear mechanism, difficult treatment and many complications. The main reasons for the current situation lie in the lack of basic research, the lack of understanding of the mechanism of cerebrospinal fluid circulation and the occurrence and development of hydrocephalus. In addition, the preoperative evaluation is not comprehensive and precise, the treat rnent plan is lack of individualized choice ? and the postoperative follow up is not strict and comprehensive, which also lim its the improvement of clinical treatment level. Therefore, based on the research progress at home and abroad, this paper reviews the current situation, classification and mechanism of hydrocephalus, new discovery of cerebrospinal fluid circula tion pathway and current treatment status, in order to provide new ideas for the research and treatment of hydrocephalus.