In this paper, we explore the use of language, its characteristics and features. In addition, a term of semantics is explained how children expand their vocabulary. Lexical development is the most dynamic in language evolvent, so it is important to know how to use lexicons, how to create lexical competencies and how to process a lexical unit well. The Picture Book is the first book a child encounters. In addition, it develops the child's vocabulary and imagination, the child creates a positive image of himself, develops attention and achieves transmission of a certain message. It emphasizes the function of dialogic reading in kindergarten, also, how to explore it and what are the guidelines. It is described that the text of the picture book must be adapted to the child's development, interesting and meaningful. It is important that the illustration is valuable to help children create a sense of beauty, realistic to make it easier to explain a particular term and creative to give the child a boost for creativity. Also, a study was conducted, in which three different picture books were analyzed considering lexical diversity. The number of occurrences, variants, and most common word combinations is expected to be in approximately equal range. In addition, it is assumed that within picture books, the same types of words, ie their frequency, represent a similar percentage. The analysis identified the most lexically demanding picture book and proved that picture books do not deviate greatly from each other lexically.