The aim of this research is to describe the language of Bosanska Posavina and thus the municipality of Orašje and to examine preschool children living in the area of Orašje and to investigate the prevalence of dialectism in the area among preschool children. Each place has its own peculiarities that distinguish it from another place. For the municipality of Orašje, speech is one of the things that distinguishes us, people from Posavina, from other people. The speech of Bosanska Posavina is unique and should therefore be explored, especially among younger children. The assumption is that dialectisms are used only by the older population, while it is assumed that the younger population is more influenced by the media, which is why children rarely use dialectisms. The research was conducted in the local kindergarten "Pčelica" in Orašje. The sample consisted of preschool children (age range from 3 to 7 years) attending the kindergarten, and the sample consisted of thirty children. The research was related to the extent to which the dialectisms of the Orašje municipality are represented in the speech of preschool children. According to the results of the respondents, nowadays children use certain dialectisms in a large percentage, while they have never heard of some of the dialectisms. The language of the Orašje municipality belongs to the Slavonian dialect, but it has its own unique characteristics, which is why it should be preserved and nurtured as much as possible. Although the dialect is still present in the area, the modern way of life has a great influence on children’s speech. Great things cannot happen overnight, but this paper was written with the hope that the richness of the speech of Bosanska Posavina will not be forgotten.