Retinal disorders of vascular origin are highly polymorphic, and in many cases they are life-threatening. They may be secondary to lesions of the vessel wall, i.e. damage to the vessel container, as in diabetic retinopathy or systemic diseases. They may be secondary to affections of the content, as in the case of hemoglobinopathies or blood viscosity anomalies.Vascularization of the retina depends on two vascular networks: the retinal circulation and the choroidal circulation. These two networks have their own specific characteristics, which are essential for retinal function. They mainly ensure the supply of oxygen and the substrates required for multiple retinal metabolic reactions. Thanks to technological advances in modern investigations, we now have a better understanding of the pathophysiological mechanisms involved in a wide range of disorders, enabling us to improve therapeutic management.