Abstract:Dry eye disease(DED)and depression(DEP), though anatomically and clinically distinct, show significant epidemiological, pathophysiological, and prognostic interplay. Their co-occurrence has risen sharply in recent years, yet the mechanisms driving this comorbidity remain under-investigated. This review systematically synthesizes current evidence, highlighting that pro-inflammatory cytokines, neuro-regulatory imbalance, mitochondrial dysfunction, and gut-microbiota dysbiosis constitute a shared molecular network, while sleep deprivation and antidepressant use further amplify the vicious cycle. By identifying limitations in existing studies, this review proposes future research directions to offer new theoretical and clinical insights for managing DED-DEP comorbidity.