In the given study we research the existence of animals and the biological groups that are considered popular and non popular animals and the criteria which the children use in order to show their preference or dislike for some animals. There were participated twenty-four children (preschoolers), which were attending three different nursery schools of Chalkidiki. The technique of the research was group interview. The findings show the existence popular and non- popular animals and moreover animals for which the children do not have a clear perspective about. Non popular animals are the reptiles, the insects, and the predators. The children give a reason why they prefer or dislike these animals. The reasons why are usually the animals' behavior, their relation with humans and additionally values related and esthetic assertions. The restricted reasoning basis of the preference, is the problem confronting. We can deal it through teaching the children with the proper pedagogical techniques for their age.