The aim of the study is to determine the extent to which the root values were included in the middle school mathematics textbooks that were recommended in the 2018 middle school mathematics curriculum by Ministry of National Education (MoNE). In this study, mathematics textbooks were assumed to be an important material in terms of development of students' intention to use root values. The data were collected from ten mathematics textbooks, including two fifth grade, three sixth grade, two seventh grade, and three eighth grades, recommended by MoNE for use in middle schools in the 2019-2020 academic year. A basic qualitative research design was used in the study. To analyze the data a content analysis process was implemented. As a result, it was found that while the values of friendship, self-control, responsibility, patriotism, and benevolence were used in the textbooks in detail and with their first meanings, there was not enough content about the values of justice, honesty, respect, and love and these values were being used differently from their first meanings. It is recommended that the content involving root values should be distributed more homogeneously to the grade levels and values should be used with their first meaning in mathematics textbooks. In addition, there should be more specific information in mathematics textbooks about how to integrate root values into a mathematics classroom.