Informed by sociocultural theory and previous research on peer scaffolding in second language (L2) learning, which largely focuses on collaborative writing in English as a second language (ESL) contexts, this study investigates the ways in which Vietnamese English as a foreign language (EFL) students provide peer scaffolding to each other during a collaborative presentation task and how they benefit from this experience. Data were collected from 12 participants through reflective reports and interviews. Content analysis of data suggests six categories of peer scaffolding behaviours among the students, namely workload sharing, pooling ideas and resources, technology support, peer feedback, support in answering the audience's questions, and affective support and the benefits that the students gained from them. The findings demonstrate that collaborative pair work creates learning conditions where peers provide mutual help, which supports previous research findings. The identified peer scaffolding behaviours also show important features suggested in the literature. Although peer scaffolding has been largely studied in L2 writing, it remains a new area of research in L2 speaking discourse. This study extends the literature to this under-researched area and offers a number of pedagogical and theoretical implications based on the findings.