This study aims to analyse the advance organizers included in the course book "Secondary School Mathematics Course Book 5"--which was prepared in accordance with 2017 secondary school mathematics curriculum and which was accepted as an educational material by Turkish Education Board of Ministry of National Education for use in 2017-2018 academic year--in terms of use, functions and forms. Employing qualitative research method, this study uses document analysis. Content analysis is used in the analysis of the research data. It was found in consequence that comparative advance organizers comparing the previous and new knowledge were heavily used in the course book.