<p>Textbooks are central instruments for imparting subject-related knowledge, but also convey social norms and might, thus, affect students’ identity formation, for instance, regarding gender roles. Studies consistently indicate an underrepresentation of female characters and the reinforcement of gender stereotypes across various subjects. This study addresses a current research gap by assessing whether contemporary mathematics textbooks align with the 2016 resolution of the Conference of Ministers of Education and Cultural Affairs, which called for the elimination of gender-stereotypical content in German mathematics textbooks. We conducted a quantitative and qualitative content analysis of 19 mathematics textbooks designed for secondary schools, i.e. Grades 5 to 9, where students usually are between ten/eleven and 15/16 years old. The quantitative results revealed an underrepresentation of female characters, particularly among adults and characters within descriptive texts. While the use of generic masculine forms further amplified these differences, it was not solely the underlying cause. The qualitative analysis identified a stereotypical distribution of roles in contexts of occupation and parental roles for adult characters and sports for child characters. However, the portrayal of mathematical activity and competence was presented in a gender-balanced manner. Overall, we found that women and men tended to reinforce traditional gender roles, while girls and boys increasingly appeared as equal peers. These findings are discussed in the context of previous research, leading to the derivation of implications for teaching practice and textbook development.</p>