This thesis deals with the characteristics and comparisons of Kušan's novels for children and films. Ivan Kušan is the most prominent Croatian writer who writes for children and adults. Famous in the world for children‟s novels, he was the first Croatian candidate for the "Andersen". He has written eight children novels, and his first novel, „Uzbuna na Zelenom Vrhu“, published in Zagreb in 1956, was rejected by a Sarajevo publisher with explanation that it is a work that does not have an educational or literary value. Kušan‟s models in writing were Kästner, Lovrak and Twain, for whom he gave explanation, Kästner is a writer who inspired Kušan the most, and whom he loved. He builds the story inspired by the crime novels, detective story, which is a kind of tension Kušan, at the beginning of the novel, puts the puzzle that children need to solve on the principles of detective novels. In the first novel, „Uzbuna na Zelenom Vrhu“, there is something specific to look for, and that would be the thieves who committed the theft of material goods. The next novel, „Koko i duhovi“, is no longer asking for it specifically, it is seeking ghosts. Puzzles that were set, gradually get psychological profile. Then, in the novel, „Zagonetni dječak“, a new student who believes he is to blame for his friend's death, takes his identity. Kušan then becomes interested in certain mechanisms of human behavior, like, why do people lie, as in the novel „Laţeš Melita“, or human emotions in the novel „Ljubav ili smrt“. Through the analysis of the novel, it is noticeable how Kušan does not use the pattern, which he cherishes from the beginning to the end, but in his writings, we can follow a certain development of both the thematic and expressive plan. As for the adaptation of literary works, the new generation of authors who have been directing for children are television director Daniel Kušan and Tomislav Ţaja. It is not possible to adapt the book fully into the movie, because in books we can find parts with many descriptions, completed by our imagination, while in the film, imagining is limited since everything is based on visual and specific, which is why some of the characters, items and events are cut out or modified. A film for children can be defined as one intended for children and with children in title roles, while the expression of Croatian Film refers to works by Croatian authors. Children's characters in movies and television series designed for their peers, bravely set off on exciting adventures into the unknown, outsmarting the bad people, solving criminal cases with ease, which adults without their help would surely not achieve.