While teacher-student relationships tend to fade out, students spend more time working with their peers when learning at the tertiary level. In the classroom, peers have different roles, which can be assigned officially by the teacher or emerge when students start working together. Despite the tremendous benefits that peers can bring to learning results, research about peer learning comparatively scatters in the Vietnamese context. The current research combined quantitative and qualitative data to understand EFL students’ perceptions and expectations of peers’ roles in the language classroom to contribute to the knowledge of peer learning in a language classroom. 709 answers from a questionnaire revealed the model of peers’ roles in the classroom. From those findings, semi-structured in-depth group interviews were conducted with 35 students to understand their expectations for their peers in the classroom. Results show that peers play the role of a co-learner, an encourager, an explorer, and an assessor in the classroom, in which the role of a co-learner is the most prominent, stressing the recognition of peer contribution and peer sharing on learning resources and strategies. They expect their peers to bring positive emotions when working together, as well as trigger the interdependence and responsibilities that they have with each other. They are also concerned with keeping face value for their friends so that they could not lose their motivation to learn.