The sustainability of sports organizations, the successful execution of events, and budget efficiency heavily rely on unpaid volunteer human resources. This study aims to critically examine the internal, external, institutional, and socio-demographic factors shaping volunteer motivation in sports organizations within a thematic framework, addressing both positive and negative dimensions. Utilizing a thematic review design, a total of 25 high-quality studies—comprising prominent articles and postgraduate theses from the sports volunteering literature—were analyzed. The synthesis of findings reveals that the primary positive drivers of sports volunteer motivation are goal-oriented dedication, the reflection of personal values, patriotism, personal development, and career aspirations. Conversely, factors that diminish motivation and lead to volunteer disengagement include a lack of managerial professionalism within sports organizations, ambiguous job descriptions and tasks, insufficient appreciation and feedback, and operational weaknesses in logistical processes. Ultimately, the sustainability and effectiveness of volunteer systems in sports organizations depend on positioning volunteers not as temporary or auxiliary labor, but as strategic internal stakeholders who directly drive organizational success

‘’sports volunteering’’, ‘’volunteer motivation’’, ‘’obstacles’’, ‘’psychological contract’’, ‘’ethical violations’’