Genetic diseases are congenital or acquired hereditary diseases that result from structural/functional disorders of the human genome. Today, the genetic factors that play a role in many diseases are being highlighted with the rapid progress in the field of genetics science. It becomes increasingly important that physicians from all disciplines have knowledge about the basic principles of genetics, patterns of inheritance, etc., so that they can follow the new developments. In genetic eye diseases, ophthalmologists should know the basic clinical and recently rapidly developing genetic characteristics of these diseases in order to properly approach the diagnosis and treatment and to provide genetic counseling. In this paper, anterior segment eye diseases of genetic origin are reviewed, and aniridia, anterior segment dysgenesis, glaucoma, corneal dystrophies, cataract, ectopia lentis, myopia, and other refractive errors are covered.