During the past several years, the importance of practicum as a vital proportion of the preservice teacher education program has been increasingly emphasized. There have been a number of initiatives for supporting preservice teachers. Among these, peer based relationship is increasingly emerged as an innovative strategy to provide additional support to preservice teachers. This paper reports on part of a larger study which investigated the impact of peer mentoring in the context of Vietnam. Using mixed methods research design, the study investigated the impact of a peer mentoring model on the preservice teachers' perceptions of their psychosocial support from their peers during their practicum in Vietnam. A peer mentoring model was implemented with a group of preservice teachers of English as a Foreign Language (EFL). Data were collected from questionnaires and focus group interview with both a group of formally peer mentored preservice teachers and a group of formally non-peer mentored. The results revealed the preservice EFL teachers in the experimental group perceived more psychosocial support from their peer than those in the control group. The study affirms the empirical evidence for implementing a peer mentoring model for preservice EFL teachers during the practicum and echoes the need for a reform in the practicum. (Contains 2 tables.)