This study aims to examine the views of preservice primary school teachers about the integration of children's literature in mathematics teaching. The views of the participants were collected before and after the use of a course outline based on the integration of mathematics with children's literature. The study had a qualitative research design, and the opinions of the preservice teachers were evaluated extensively through the case study. The data were obtained through mathematics lesson plans and open-ended questionnaires developed about children's literature. The items in the first form were concerned with the experiences of the pre-service teachers about the integration of children's literature in mathematics, their views on the selection process of children's books, and their expectations and evaluations regarding the practice. The second form was aimed to share their experiences following the implementation and to get their opinions about the teaching process which reflected the relationship between children's literature and mathematics. According to the findings, the views of the participants are grouped into the following four dimensions: book selection criteria and process, pedagogical effect, integration process, possible barriers, and limitations. It is found that the participants have difficulty in choosing children's books that provide opportunities for learning mathematics to the children. Following the implementation, they emphasized the pedagogical benefits of the practice such as increasing children's motivation and interests in learning mathematics. During the integration process, they mostly made use of the context of the books. Some of them employed books to teach mathematical concepts and skills. However, the books were mostly used to get attraction, make courses more fun, and increase student motivation. To use children's books as an effective tool to support conceptual understanding in the mathematics teaching process, pre-service and in-service teachers should be provided with necessary training and experience.