Children's books have a special importance because they are the first books in which children learn
their native language and are effective in gaining reading habits. For this reason, books written for
children are expected to contain certain elements. Within the framework of this research, the
children's book titled Kayıp Masalın Şifresi [The Code of the Lost Tale], written by Mahir Çipil, was
examined in terms of containing the basic elements of children's literature. In this study, which is a
qualitative research, document analysis, one of the data collection methods, was used. The analysis
includes external structure (size of the book, cover design, paper quality, letters, page layout and
illustrations), internal structure (theme, subject, heroes, setting, fiction and message), language and
expression (proverbs, idioms, reduplications, similes, reinforcements). It is structured under three
headings: use of unknown words, use of slang words, bad expression, spelling mistakes and
metaphors). According to the review, the qualities of the external structure of the book largely reflect
the principles that children's books should carry. When the internal structure was examined, it was
determined that although there were two separate plots in the book, the events were not mixed
together and were in accordance with the principles of children's literature. When the book was
examined in terms of language and expression, it was determined that the most used expressions
were idioms, reduplications, reinforcements and analogies, respectively. When we look at the book
in general, the small number of spelling errors and expression errors shows that careful language is
used. Of the book; being rich in terms of idioms, reduplications, reinforcements, similes, metaphors
and riddles, which are among the riches of the native language, makes the children's novel called
Kayıp Masalın Şifresi compatible with the principles of children's literature in terms of language and
expression.