Although associations between visual impairment (VI) and suicide are posited, specific risks across the sight-threatening eye disease (STED) spectrum remain to be assessed. We determined whether individuals with STED die more often by suicide than do other people and assessed the temporal associations. A nationwide, population-based cohort study. All persons aged 40 years or older in South Korea from 2010 to2020. Persons diagnosed with STEDs (i.e., glaucoma, exudative age-related macular degeneration [AMD], or diabetic retinopathy [DR]) were identified in the Korean National Health Insurance (NHI) service database. Both NHI health checkup records and the National Disability Registration were used for coexisting severe VI. Death by suicide was defined as diagnostic codes as recorded in the Korea National Statistical Office. Incidence rate ratios (IRRs) were estimated by quasi-Poisson regressions and adjusted for sociodemographics, comorbidity, psychiatric diagnoses, and VI. The temporal relationship between time since first STED diagnosis and suicide risk was determined by identifying patients with STED newly diagnosed during the period from 2010 to2011. The IRR of death by suicide in people with STED relative to those without. Of the 2.8 million people (45% male) observed for 24 300 969 person-years, 13 205 died by suicide. Among them, 34% (n= 4514) had a STED diagnosis, for a suicide rate of 69 per 100 000 person-years (95% confidence interval [CI], 67-72), relative to 51 per 100 000 person-years (95% CI, 50-52) for non-STED individuals. People with STED had an adjusted IRR of 1.33 (95% CI, 1.26-1.41) relative to those without. The largest excess adjusted IRR of suicide mortality was that for DR (1.40, 95% CI, 1.29-1.52). For exudative AMD, the adjusted IRR was 1.20 (95% CI, 1.04-1.39), whereas for glaucoma, the corresponding value was 1.09 (95% CI, 1.02-1.17). With coexisting severe VI, the IRR for any STED was 1.49 (95% CI, 1.29-1.73). The highest suicide hazard ratio was between 3 and 6 months postdiagnosis (5.33; 95% CI, 4.59-6.20). In South Korea between 2010 and 2020, a higher suicide rate was evident among those with diagnosed STED than for persons not so diagnosed. The author(s) have no proprietary or commercial interest in any materials discussed in this article.