Abstract: Disclosed are methods for treating or preventing ocular neovascularization in a subject at risk. The method comprises administering to the subject an effective amount of omega-3 polyunsaturated fatty acid to thereby treat or prevent the ocular neovascularization. This method is suitable for treating or preventing retinopathy of prematurity, retina vein occlusion, sickle cell retinopathy, choroidal neovascularization, radiation retinopathy, microangiopathy, retinal hyperoxia, diabetic retinopathy, and age related macular degeneration. Preferably the methods are applied to premature infants, especially those exposed to high levels of oxygen, to treat or prevent ocular neovascularization results from retinopathy of prematurity. Preferably, the omega-3 polyunsaturated fatty acid is administered at high dose, periodically (e.g. from birth) over a prolonged period of time, until the eye is fully vascularized, or to the age of 1 year. Appropriate routes of administration include oral and intravenous administration.