Choroidal neovascular membrane (CNVM) or choroidal neovascularization (CNV) is the formation of new blood vessels that grow beneath the retina and threaten the central vision. Choroidal blood vessels are classified on the basis of their morphology, the type of their branching, the presence of vascular loops, localizations of loops, and according to their capillary density, thickness and appearance. This chapter covers the etiology and epidemiology, symptoms and signs, types of choroidal neovascularization, diagnostics, morphological forms of neovascularizations, examples of eyes with neovascularization shown by the OCTA, and therapy. Choroidal neovascularization is the most frequently seen in the age-related macular degeneration (ARMD), in its exudative form, where abnormal blood vessels grow from the choriocapillaris.