The study aims to reveal how teachers and teacher candidates epistemologically evaluate and define conspiracy, paranormal, and pseudoscientific beliefs. To this end, interviews were conducted in a qualitatively designed study, and the data were analyzed using content analysis methods. It was observed that participants tended to believe in conspiracy theories, paranormal phenomena, and pseudoscientific claims defined as irrational beliefs in certain respects. It was concluded that participants generally adopted a traditionalist belief in some epistemological dimensions. However, it was observed that they developed a more constructivist belief in some dimensions. In this context, the research results show that their epistemological beliefs about knowledge and knowledge acquisition influence their stance toward irrational knowledge. It was observed that individuals with developed epistemological beliefs approach the information they encounter in a more critical and questioning manner.