The integration of children's literature, specifically mathematical story picture books, in mathematics education has demonstrated significant benefits. Nevertheless, its actual implementation largely hinges on teachers' beliefs. This exploratory mixed-methods study examines the beliefs of 78 teachers regarding the integration of children's literature into mathematics teaching and learning, with a focus on identifying its barriers and enablers. Data were collected through an open-ended survey and semi-structured interviews and analyzed using thematic analysis framed by the concept of belief indication. The study identifies 15 barriers (across five themes) and 16 enablers (across six themes) that, teachers believe, affect their decisions to integrate children's literature into mathematics teaching and learning. This paper contextualizes the findings within the Theory of Planned Behavior (TPB), a framework from social psychology, to provide actionable recommendations and compare findings from studies conducted in Asian and Western countries. Ultimately, this research offers a broader understanding of teachers' behaviors and their receptiveness to educational reforms, such as the integration of children's literature, across diverse cultural and international settings.