Despite the benefits of sport, there is a limited understanding of how to initiate and maintain sport participation among youth with physical disabilities (PDs). Peers and the unique support they provide may be one way to meet these needs. However, research on peer support in the context of sport among youth with PDs is lacking. The purpose of this study was to qualitatively explore the role of peers in supporting youth with PD's sport participation using self-determination theory (SDT) as the guiding framework. Eight youth with PD from the Greater Toronto Area were interviewed using verbal discussion and relational mapping to elicit further detail. Data were analyzed using an inductive-deductive thematic analysis (Braun & Clarke, 2006), with SDT as the deductive guiding framework. The youth (aged 13 to 18 years) participated in a variety of sports, predominantly wheelchair basketball (n = 4) and at a recreational level (n = 6). Key themes and sub-themes of the youths' progression through sport and the changing role of peers throughout their sport experiences were expressed. These included youths' development through sport, multi-level need thwarting (e.g., victimization) and supporting (e.g., socialization) behaviours, and the manifestation of their sport internalization (e.g., identifying with teammates). Suggestions for improving and creating new sport programs for youth with PD were provided such as having more opportunities for reverse integration or inclusive programs. Overall, peers may assist in creating positive sport experiences for youth with PD by fulfilling the three basic psychological needs of SDT.