Preschool aged children can express certain problems in behaviour which can be classified in two basic categories, internalized and externalized behaviour problems. In order to recognize that a child has a certain problem in behaviour and to know how to act preventively, preschool teachers need to have certain skills which will help them better manage those children. The paper presents research, whose results mach those results of some other existing research, regarding hypotheses that refers to preschool teachers who have proven to be able to recognize children with behavioral problems. However, the majority of research participants still believe that the role of preschool teachers in prevention of these problems isn't enough. The child's family, in which they initially learn the basic skills of functioning in society and socialization, has the greatest influence on the child. Considering the family structure, satisfaction of some family members and their interpersonal relations, a family can also present a risk factor for developing behavioral problems. Except for the family, the cause of problems can in a certain measure be a child's biological predisposition, as well as the environmental impact. Still, most of the research participants consider that peers don't have such a big impact on occurrence of problems during preschool age because their impact becomes bigger as the children are older. Internalized problems are even considered more dangerous than the externalized problems because they are harder to spot and can lead to long term effects on their psychological functioning. The best way to prevent, both internalized or externalized problems, is by organizing and involving children in different activities or sports events. Further, in what most participants agree is that if preschool teacher tries, he can have a big impact on a child's behaviour, which can encourage preschool teachers in their everyday work.