Optic nerve sheath fenestration(ONSF), also known as optic nerve sheath decompression, was first proposed by Wecker. The procedure involves cutting incisions or windows in the retrabulbar optic nerve sheath to release the cerebral spinal fluid from the subarachnoid space of the optic nerve, reducing the pressure surrounding the optic nerve. With the development of surgical instruments and procedures, the safety of ONSF has been significantly improved with infrequent complications. Through the past three decades, more and more ophthalmologists realized that ONSF is an effective surgical treatment to stabilize or improve visual loss in idiopathic intracranial hypertension(IIH). Additionally, much progress in the use of ONSF has been made on secondary intracranial hypertension due to cerebral venous sinus occlusion, Cryptococcal meningitis, and intracranial mass or tumors. In this paper we review the application of ONSF in IIH, and secondary intracranial hypertension. From the review, it indicates ONSF is a good surgical alternative for ophthalmologists. It also indicates that ONSF can be used to prevent or halt progressive visual loss associated with intracranial hypertension, particularly when other treatment modalities fail to protect vision.