As primary providers of preventive and curative community case management services in low- and middle-income countries (LMICs), community health workers (CHWs) have emerged as a formalised part of the health system (HS). However, discourses on their practices as formalised cadres of the HS are limited. Therefore, we examined their role in care, referral (to clinics) and rehabilitation of severe acute malnutrition (SAM) cases. Focusing on SAM was essential since it is a global public health problem associated with 30% of all South Africa's (SA's) child deaths in 2015. Guided by a policy analysis framework, a qualitative case study was conducted in two rural subdistricts of North West province. From April to August 2016, data collected from CHW's training manuals and guideline reviews, 20 patient record reviews and 15 in-depth interviews with four CHW leaders and 11 CHWs. Using thematic content analysis which was guided by the Walt and Gilson policy triangle, data was manually analysed to derive emerging themes on case management and administrative structures. The study found that although CHWs were responsible for identifying, referring, and rehabilitating SAM cases, they neglected curative roles of stabilisation before referral and treatment of uncomplicated cases. Such limitations resulted from restrictive CHW policies, inadequate training, lack of supportive supervision and essential resources. Concurrently, the CHW program was based on weak operational and administrative structures which challenged CHWs practices. Poor curative components and weak operational structures in this context compromised the use of CHWs in LMICs to strengthen primary healthcare. If CHWs are to contribute to Sustainable Development Goal (SDG) 3 by reducing SAM mortality, strategies on community management of acute malnutrition coupled with thorough training, supportive supervision, firm operational structures, adequate resources and providers' motivation should be adopted by governments.