A picture book is the first book a child comes into contact with and it is very important for their further development. The child gets to know the real world through picture books. They enable the development of the child's imagination, awaken emotions and the creation of their own ideas, which form the basis for building the child's character. It also encourages the aesthetic-artistic aspect of their development. Ilustrations and text of high quality are both of importance for a well-deigned picutre book. Good illustrations and text can attract and retain the child's attention to continue reading and thinking about what they read. The entire picture book must act as a harmoniuos whole and the child must understand it as a work in which the visual and textual components are of equal value. The theoretical part of this thesis addresses what a picture book is, the role of a picture book, the function of the picture book and the importance of reading a picture book. It further addresses, the categorization of picture books, the differences between illustrated books and picture books, the importance of illustrations and the realtionship between the text and the illustrations in a picture book. Additionally, the history of the picture book in Croatia and the world is addressed as well as looking into prominent Croatian illustrators. The second part of the thesis is the practical part that includes the goal of the work, the process of creation of a picture book, the creation of a storyboard, and the final version my own picture book entitled Aspen on the planet Kai. Before the creation of the storyboard, I came up with a title which I wanted to be unusual and interesting to a child. The picture book is of an instructive nature and reinforces the reader's awareness of the importance of brushing teeth, but in a funway with the addition of surreal elements that will spark the child's interest. It is intended for children aged 5 to 7 years of age. This makes the text more demanding to read. Children of that age have a broader understaning of the world, so some illustrations enable deeper reflections and the inclusion of the child's imagination. The art technique used to design the picture book is watercolor pencils. Both the illustrations and the text were subsequenlty processed in the program Bojanje 3D. The text is written artistically using rhyme so that children can remember it more easily.