Aim: The aim of this metasynthesis was to identify, analyze and synthesize the qualitative findings from original research studies addressing student nurses' experiences with a peer mentoring program in their clinical placements. Background: Students' positive experiences from clinical placement studies, are often associated with quality of clinical mentoring and learning environments. However, nurse mentors struggle to find sufficient time for mentoring student nurses. Establishing a peer mentoring program, may provide additional mentoring and strengthen clinical placement as learning environment. A peer mentoring program entails, that senior student nurses at one level act as a supportive mentor and serve as role models for fellow novice student nurses at a lower level. Design: A flexible descriptive design was applied for this metasynthesis. Methods: By using the same search strategy, systematic searches were made in the following electronic databases: CINAHL, MEDLINE OVID, Embase, ERIC, Scopus, Oria andSveMed+ . Ten articles met the eligibility criteria, reporting findings from altogether 203 student mentors and 446 student mentees. Extracted information (data) from the articles were analyzed in lines with Graneheim & Lundmans' five phases of thematic analysis of data. Results: The analysis resulted in two overarching themes characterizing students' experiences. Student mentors experienced that participating in peer mentoring had been Strengthening the road to becoming a professional nurse. Student mentees experienced that participating in peer mentoring had been Strengthening the studying and learner role in clinical placement. The themes covering student mentors experience were: Understanding and integrating nursing competence; Realizing the need to be mentored and supported as mentors; Understanding the content and complexity of clinical mentoring. The themes covering student mentees experience were: Reaching further for clinical competence and self-confidence; Taking advantage of mentoring and learning situations; Understanding the importance of learning conditions and their own learning responsibility. All themes were further characterized with sub-themes. Conclusions: The findings from this metasynthesis are in general positive for both student mentors and mentees andboth student groups experienced to benefit from participating in the peer mentoring program.