Abstract： Objective To evaluate the clinical features and treatment outcomes of ocular posteriorsegment syphilis.Methods The clinical data of 24 patients with active ocular syphilis wereretrospectively reviewed.The diagnosis was made first in eye clinic,and verified by treponema pallidumparticle agglutination(TPPA)and rapid plasma reagin(RPR).The patients,17 males and 7 females,aged from 30 to 63 years with an average of 47.6 years.The duration of symptoms ranged from 3 days to2 years with an average of 5.8 months(≤1 month,7 cases;1-3 month,5 cases;3-6 months,5 cases;>6 months,7 cases).There were 18 bilateral cases and 6 unilateral cases.The result of humanimmunodeficiency virus(HIV)test was negative for all cases.Twenty-three patients received systemicpenicillin therapy and 1 patient was treated with oral erythromycin due to penicillin allergy.Beforetreatment,the mean visual acuity was 0.17±0.1 9,the mean titer of RPR was 1:84.The follow-up periodwas half a year.Results The major ocular manifestations included bilateral(16 cases)or unilateral(1case)chorioretinitis,unilateral retinal vasculitis(2 cases),unilateral neuroretinitis(2 cases),andbilateral(2 cases)or unilateral(1 case)optic neuritis.The mean follow-up visual acuity was 0.60±0.29,the mean follow-up titer of RPR was 1:18.8.Some patients had got the diagnosis and prompt treatment atthe early stage of the disease and their visual acuity recoveried very well.Conclusions The majormanifestion of ocular posterior segment syphilis is chorioretinitis.It is important tO consider the possibilityof syphilis when patients have inflammation of posterior segment.Prompt serology examination andpenicillin treatment are the keys to cure ocular syphilis.