Student teachers consider teacher training as an important part of teacher education. Despite this, students’ explicit descriptions of quality in mentoring have not been paid much attention in the Swedish context. This study aims to contribute with knowledge of student teachers’ expressions of quality in mentoring during the teacher training program. Two focus group interviews and seven individual interviews were conducted with student teachers specializing in teaching grades F–3 and 4–6, in teacher training schools that participated in the trial activities in Sweden. Their statements have been analysed based on the theory of social representations. The result shows that three social representations appear: Qualitative mentoring is characterized by a) student’s professional development, b) collegial cooperation, and c) trust. These social representations influence students’ expectations of mentoring and its design. Although the students want to be seen as colleagues, they expect mentors to decide when, where and how mentoring should be carried out, and to have a distinct feeling to use the right type of mentoring at the right time. The mixed professional roles, which is highlighted by the students but seem to be implicit, calls for different forms of mentoring strategies that need to be explicit for both the mentor and the student.