Importance: Common pathophysiological mechanisms may be responsible for immune dysregulation in both thyroid disease and uveitis. Studies investigating a possible association are limited. Objective: To determine the association between thyroid disease and uveitis. Design, Setting, and Participants: A retrospective, population-based case-control study was conducted from January 1, 2006, to December 31, 2007, among 217 061 members of the Kaiser Permanente Hawaii health system during the study period. A clinical diagnosis of uveitis was determined through a query of the electronic medical record followed by individual medical record review for confirmation by a uveitis specialist. Thyroid disease was determined based on International Classification of Diseases, Ninth Revision, coding. Two control groups were chosen at a 4:1 ratio for comparison with patients with uveitis. A logistic regression analysis was performed with uveitis as the main outcome variable and thyroid disease as the main predictor variable, while adjusting for age, sex, race, smoking status, and history of autoimmune disease. Data analysis was conducted between 2014 and 2016. Main Outcomes and Measures: A diagnosis of thyroid disease among patients with uveitis and respective controls. Results: Of the 224 patients with uveitis (127 women and 97 men; mean [SD] age, 54.1 [17.8] years) identified during the study period, 29 (12.9%) had a diagnosis of thyroid disease, compared with 62 of 896 patients (6.9%) in the control group (P = .01) and 78 of 896 patients (8.7%) in the ophthalmology clinic control group (P = .06). Using the general Kaiser Permanente Hawaii population control group, patients who had thyroid disease had a 1.7-fold (95% CI, 1.03-2.80; P = .04) higher odds of having uveitis compared with patients who did not have thyroid disease when controlling for age, sex, race, smoking status, and autoimmune disease. A similar association was found using the ophthalmology clinic control group (odds ratio, 1.8; 95% CI, 1.1-2.9; P = .02) while adjusting for these factors. Conclusions and Relevance: These findings suggest that a history of thyroid disease has a weak to moderate association with uveitis. Similar autoimmune mechanisms could explain the pathogenesis of both conditions. If future studies corroborate these findings, they may have further clinical implications in the laboratory workup of uveitis.