Understanding the structure of our mother tongue is essential for many reasons. Therefore, the study of syntax is one of the fundamental contents of language classes in Secondary Education in Spain. However, the motivation and interest that students show towards it is often lacking. The aim of this study is twofold: 1) to describe teachers' and students' perceptions of the teaching of syntax in the Spanish Language and Literature class, and 2) to assess which factors may have an impact on learning success. For this purpose, a mixed quantitative-qualitative research design is used. The responses of students and teachers of Secondary Education and Pre-university Education collected by means of different types of surveys are analysed. The results show a widespread concern for the motivational factor, a diversity of opinions and general agreement with the methodology applied. However, a significant proportion of the student sample is unaware of the usefulness of learning syntactic content. Traditional methodologies continue to prevail in the classrooms studied, although innovative methodologies are related to more motivated students. A significant link is observed between motivation, teaching methodology and understanding of the functionality of syntax. Limitations of the study are commented upon, and theoretical and practical implications are discussed.