Since textbooks are the main reference material in English language teaching, they are considered to be an important element of this process, so the selection of the right and effective textbook is equally important. However, in most cases textbooks are defined and prescribed by the main authority of the education system, school administrators, a responsible teacher or similar stakeholders, and students' preferences are not included in the process. The aim of this study is to examine the ideas of English language learners toward textbooks and their epistemological beliefs. The questionnaire of textbook preference in foreign language teaching (Oruç & Yavuz, 2013) and the central epistemological beliefs scale (Oksal, Şenşekerci, & Bilgin, 2006) were administered to determine the participants' textbook preferences and epistemological beliefs. The findings of the study showed that students attached great importance to the preference of textbooks and scored medium or high on the administered instrument. It was reported that most of the participants regarded the ideal textbook as “an activity source for students to practice and communicate” and consider the student book as the main component of the textbook package. Similarly, most of the participants stated that the content of textbooks should be function-based, and speaking was emphasized as the main language skill that should be addressed in textbooks, followed by reading, listening and writing skills according to the average scores. The findings on epistemological beliefs showed that students had medium level epistemological beliefs and that the "belief in supernatural powers" dimension was the primary source of knowledge. In the light of these findings and the existing studies in the literature, it was stated that student participation in textbook preference is important and necessary and that there may be a bidirectional relationship between textbook preference and students' epistemological beliefs that can affect each other.

Textbook, epistemological belief, English language teaching, university students