Background: The cause of cell death is thought to be due to the pathological apoptotic process in Retinal Ganglion Cells (RGCs), but how the exact mechanism of what is most influential is still not explained. Objective: This study aimed to explain the mechanism of RGCs apoptosis Rattus Norvegicus which is thought to underlie the occurrence of ethambutol toxic optic neuropathy. Methods: A total of 42 male, adult Rattus norvegicus Sprague-Dawley strains were divided into 6 groups with 3 control groups and 3 treatment groups in a randomized design with time series test. The treatment groups were given ethambutol 15 mg/kg/day for each group within 5, 10 and 15 days orally using a gauge.Expressions of SOD2, MDA, PKC δ, p53, Cyt c, Caspase 3 and apoptosis were examined by immunohistochemical methods. Results: Ethambutol affected significant decreased expression of SOD2 with p=0.002 in 5 days, p=0.013 in 10 days and p=0.018 in 15 days; significant increased MDA in 5 days with p=0.05, 10 days with p=0.017, 15 days with p=0.002; significant increased p53 in 5 days with p=0.012, 10 days with p=0.002, 15 days with p=0.001; significant increased Cyt c in 5 days with p=0.004, 10 days with p=0.001, 15 days with p=0.001; significant increased Caspase 3 in 5 days with p=0.001, 10 days with p=0.003, 15 days with p=0.001 and apoptosis in 5 days with p=0.001, 10 days with p=0.001, 15 days with p=0.001. Conclusion: The mechanism of apoptosis of RGCs caused by ethambutol was showed via decreased expression SOD2, increased expression of MDA, p 53, Cyt c, Caspase 3 andapoptosis. These biomarkers are essential to detect apoptosis as one of mechanism in cell death.