This study examines the role of epistemological beliefs in moderating the relationship between critical and creative thinking among science teachers. It aims to explore how advancements in understanding knowledge influence these cognitive skills. The primary focus is on the extent to which epistemological beliefs impact critical and creative thinking, highlighting the need for a deeper grasp of knowledge to foster these skills. A mixed-methods approach is used, combining qualitative and quantitative data within a pragmatic framework to provide a comprehensive view. The sample includes science teachers from Selçuklu, Meram, and Karatay districts in Konya, Türkiye. Quantitative data were gathered using the Epistemological Beliefs Scale, the Critical Thinking Scale, and the Creative Thinking Scale. Results show that epistemological beliefs significantly influence critical and creative thinking, suggesting that these skills are closely tied to epistemological development. Qualitative findings support this, indicating that a solid epistemological foundation is essential for both types of thinking. Additionally, the study finds that authoritarian teaching methods suppress critical thinking, while student-centered strategies enhance it. To promote critical and creative thinking, science teachers should develop their epistemological beliefs and create an environment that encourages open discussion and diverse perspectives.