Negative assortative mating for refractive errors of the eyes of 1241 married couples was discovered in the urban region of the South Moravian region. 46 married couples were myopic, 55 hyperopic, 73 astigmatic, 175 had combinations of refractive errors, 261 were emetropic and 631 weremixed. Negative assortative mating is highly significant (chi-square P < 0.001). It is more significant for urban population.Positive selection foremetropic marriedcouples playsmoreimportant role in urban peoples than in citizans.

        Key words: assortative mating,myopia, astigmatism, hyperopia, emetropia, urban population, citizyans, Moravia