<p>Mental health support workers (MHSWs) are an important workforce within the mental health care system. Research shows that support services delivered by MHSWs are effective at improving the outcomes of individuals with mental illness. However, there is also literature suggesting that this group of workers are facing many challenges in their roles. This qualitative systematic review sought to explore, analyze and synthesize available primary research literature on the experiences of MHSWs with the aim of identifying the barriers to and facilitators of effective delivery of their roles. An electronic search of Medline, CINAHL, PsycINFO, and Web of Science was conducted for studies from database inception to March 28, 2025. Additional search was conducted via Google Scholar and in the reference lists of the included articles. The Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Qualitative Research was used to assess the methodological quality of included articles. Fourteen primary research articles met the eligibility criteria and were included in the review. Data synthesis from these articles generated 116 findings and 20 categories, which were aggregated into four synthesized findings: a supportive work environment, service user care barriers, professional and role-related barriers, and operational and support barriers. The review highlights the importance of a supportive work environment in the delivery of support work roles. However, several barriers were also identified and recommendations that can be used to inform practice and policies of mental health support work provided. If addressed, the identified barriers can be translated into facilitators that would enhance the provision of quality care to people with mental illness and enhance the overall job satisfaction of MHSWs.</p>