Based on the neurovascular unit (NVU), neurovascular coupling functions as a barrier to maintain the homeostasis of the microenvironment by regulating the signaling and metabolic activity of nerve cells and capillaries. Widely dispersed across the retina, the neurovascular unit is essential to preserving its physiologically normal function. A disturbance in retinal neurovascular homeostasis produced by a range of factors can result in a variety of retinal disorders, such as diabetic retinopathy (DR), glaucoma, retinitis pigmentosa (RP) and age-related macular degeneration (AMD). The retina also has a widespread distribution of brain-derived neurotrophic factor (BDNF), which functions to promote neuron growth and repair damage by binding to its receptor TrkB. In recent years, BDNF was found to play a protective role against damage in early stage of retinal neurovascular homeostasis imbalance, often known as the neurodegenerative stage. It also helps to reduce the production of pro-angiogenic substances of neurological origin and offers a fresh approach for the early detection and treatment of associated eye disorders.