Recent years have seen increasing momentum towards task shifting of basic health services, including using community health workers (CHW) to diagnose and treat common childhood illnesses. Yet few studies have examined the role of traditional healers in meeting families' and communities' health needs and liaising with the formal health system. We examine these issues in Tshopo Province in the Democratic Republic of the Congo, a country with high rates of child mortality (104 deaths per 1000 live births). We conducted 127 in-depth interviews and eight focus group discussions with a range of community members (mothers, fathers and grandmothers of children under 5 years of age) and health providers (CHWs, traditional healers, doctors and nurses) on topics related to care seeking and case management for childhood illness and malnutrition, and analysed them iteratively using thematic content analysis. We find significant divergence between biomedical descriptions of child illness and concepts held by community members, who distinguished between local illnesses and so-called 'white man's diseases.' Traditional healers were far less costly and more geographically accessible to families than were biomedical health providers, and usually served as families' first recourse after home care. Services provided by traditional healers were also more comprehensive than services provided by CHWs, as the traditional medicine sphere recognised and encompassed care for 'modern' diseases (but not vice versa). Meanwhile, CHWs did not receive adequate training, supervision or supplies to provide child health services. Considering their accessibility, acceptability, affordability and ability to recognise all domains of illness (biomedical and spiritual), traditional healers can be seen as the de facto CHWs in Tshopo Province. National and international health policymakers should account for and involve this cadre of health workers when planning child health services and seeking to implement policies and programmes that genuinely engage with community health systems.