There is a strong focus on primary health care (PHC), as rooted in a commitment to social justice and equity, to reduce social inequalities in health. Within PHC, interprofessional collaboration is emphasized to achieve these objectives. Social workers are a renewed partner within these collaborations, as principles of social justice and human rights are the core of this profession. However, it is unknown if and how social work implements these principles in primary health care settings. This systematic literature review examined the existing literature on the role of social work in primary health care settings on themes of social justice. Our results emphasize how valuable the presence of social workers in primary health care is because of their broad perspective on health. At the same time, we also reveal a few points of concern, as their focus on social justice remains rather individual. This review suggests the strengthening of a social justice based approach in primary health care, which is an issue that should be shared with other healthcare professionals. We discuss implications for practice, research and policy.