Speech can shape a person's way of thinking and the way he understands the world around him, but also himself. Speech itself can begin the process of socializing a child with his community and involving him to participate in it. The child must learn to listen, before he learns to speak in order for the development of his speech to be valid and go its course. Speech represents human sound-optimal communication that is shaped by rhythmic units that are divided into syllables, words, and sentences. As such, he is characteristic of man, the only living being who has organs and a psyche capable of projecting speech (Škarić 2006). In addition, speech plays an important role in people's lives, so it is important that every parent is aware of the early development of speech in children because they are the ones who, along with educators and the rest of the environment will encourage development (Škarić 2007). There will be no speech if there is no influence of the social environment. For normal speech development it is necessary to be in a human environment, so the child should constantly expand the circle of people with whom he comes into contact and with whom he communicates in his mother tongue. Such experiences enrich his life with new experiences, encourage him and encourage his communication and speaking skills in his mother tongue (Rade, 2003). This thesis deals with a theoretical overview of the basic assumptions about the mother tongue and indicates its connection with the development of speech in children, it will also indicate its impact on speech development, and its importance in the overall development of the child.