The mitochondrial unfolded protein response(UPRmt)represents a crucial intracellular stress response mechanism that plays a fundamental role in maintaining mitochondrial and cellular homeostasis. Growing evidence suggests that dysregulation of UPRmt contributes significantly to the pathogenesis of various systemic disorders, including neurodegenerative diseases such as Parkinson's and Alzheimer's diseases, as well as age-related pathologies. Emerging research has particularly highlighted the involvement of UPRmt in ocular diseases, including cataracts, glaucoma, and diabetic retinopathy. This comprehensive review examines the physiological functions of UPRmt and its regulatory mechanisms in age-related eye diseases. The roles of key UPRmt downstream effector molecules in ocular cell populations such as lens epithelial cells, retinal pigment epithelial cells, and retinal ganglion cells are systematically analyzed. Importantly, the dual regulatory nature of UPRmt in ocular pathophysiology is discussed, that is, its moderate activation promotes mitochondrial homeostasis, mitigates oxidative stress, and suppresses inflammatory responses, its chronic or excessive activation triggers apoptotic pathways, induces metabolic dysfunction, and ultimately accelerates disease progression. By elucidating these mechanisms, our review provides novel insights into ocular disease pathogenesis and proposes potential therapeutic strategies targeting UPRmt modulation for the prevention and treatment of age-related eye disorders.