Silicone oil has been used as a safe and effective long-term vitreous substitute(VS)for more than 50 years. Clinically, it is currently widely used in surgical patients with severe ocular trauma and various complex vitreoretinal diseases, which has improved the prognosis of some previously incurable eye diseases. A series of toxic effects caused by the long-term retention of silicone oil in the vitreous cavity have attracted great attention. Based on the physicochemical properties of silicone oil, this review will analyze and summarize the toxic effects of silicone oil on the optic nerve, as well as its mechanism.