In 2014, the Neuro-Ophthalmology Group of the Chinese Ophthalmological Society of the Chinese Medical Association formulated the Expert Consensus on the Diagnosis and Treatment of Optic Neuritis, pointing out that infectious and infection-related optic neuritis is an important etiological type of optic neuritis.In recent years, the incidence of syphilis has been increasing year by year.In 2016, the incidence of syphilis in China was 32.2/100 000.Syphilitic optic neuritis (SON) has become a type of infectious optic neuritis that cannot be ignored by ophthalmologists.SON is caused by Treponema pallidum invading the optic nerve and its surrounding sheath, and is a part of ocular syphilis and neurosyphilis.The clinical manifestations of SON are variable and can imitate various infectious or autoimmune optic nerve diseases.SON is called universal imitator, and its misdiagnosis rate and omission diagnosis rate are relatively high.Therefore, the Neuro-Ophthalmology Group of the Chinese Ophthalmological Society of the Chinese Medical Association organized the members of the expert group to extensively investigate and summarize the problems and difficulties existing in the diagnosis and treatment of SON patients in clinical practice nationwide via emails and online meetings.After many discussions and more than one year of repeated revisions, an expert consensus on the diagnosis and treatment of SON was formulated, focusing on the clinical manifestations, diagnostic criteria, treatment plans and follow-up of SON, which provides important guidance for the promotion of standardized diagnosis and treatment of this disease.