Diabetic retinopathy (DR) significantly impairs patients' psychological well-being and quality of life, yet the association between DR and suicidal ideation (SI) remains unclear. This study investigates this potential association and its consistency across various population subgroups. We performed a cross-sectional analysis using data from 7 cycles (2005-2006 through 2017-2018) of the National Health and Nutrition Examination Survey. The final analytical sample comprised 4006 adults with diabetes. Weighted multivariate regression analysis was used to assess the association between DR and SI. Subgroup analyses, interaction analyses, and a series of sensitivity analyses were used to explore the stability of the results. After sequential adjustment for demographic characteristics, lifestyle factors, comorbidities, and depressive symptoms, DR was associated with an increased risk for SI (odds ratio = 1.70, 95% confidence interval: 1.08-2.68, P = .023). Subgroup analyses showed generally consistent positive associations across most subgroups, and no significant interaction remained after correction for multiple comparisons. Sensitivity analyses confirmed robustness (multiple imputation and diabetes-related adjustment remained significant). In a sensitivity analysis using a fundus photography-based DR definition (limited to 2005-2008 cycles with a small sample size and few SI events), the estimate was nonsignificant but directionally consistent (odds ratio = 1.27; P = .607). DR is associated with increased SI among United States diabetic adults, independent of depressive symptoms. Given the cross-sectional design, these findings should be interpreted cautiously and confirmed in future prospective studies.