Purpose <p>Mental health (MH) problems are the second-most prevalent work-related health issue among employees, and occupational health services are an essential source of MH support. In this scoping review, we evaluated how occupational health services and workplaces collaborate to promote good MH and prevent or reduce MH problems at the workplace.</p> Methods <p>We searched six electronic databases for scientific literature published between 2002 and 2024. We selected original research on MH issues and collaboration between occupational health services and workplaces, regardless of study design, that had been published in English in peer-reviewed journals. We conducted a scoping review and summarized the findings in tables.</p> Results <p>We screened 1181 articles and selected nine studies that met our eligibility criteria—three randomized controlled trials and six qualitative studies. Most of the studies focused on tertiary prevention, particularly return to work after sickness absence, and a few addressed primary or secondary prevention. Their topics included support for returnees, manager training, strengthening MH resources and workplace safety. Collaboration was multidisciplinary, involving various representatives from the workplace and occupational health services, and was further complemented by other relevant stakeholders. Our findings indicate that unclear processes and lack of trust impede collaboration, whereas shared goals and trust facilitate it.</p> Conclusion <p>The literature focuses more on tertiary prevention among individual employees than on primary or secondary measures. Trust, clearly established goals and roles, and a shared vision of MH support should be basic elements for collaboration and successful partnerships.</p>