The article highlights the main purpose of works written in the fantasy genre in children's literature and the influence of this genre on children's critical thinking. In the works of J. R. R. Tolkien and J. K. Rowling, who are representatives of the fantasy genre of this period, there are also motifs from myths and fairy tales. The study also reflects the appeal of J. R. R. Tolkien and Rowling to the fantasy genre in their works, the attitude of outstanding writers towards it and the moments associated with the creativity of writers.