BackgroundYoung children are at the highest risk of developing dental caries as they have a lack of autonomy over their diet and oral hygiene practices. Dental caries develops over time due to demineralization of tooth substance (enamel), which results from acid production during sugar metabolism by bacteria. Early onset of dental caries often results in asymptomatic presentation, but if left untreated, it can result in severe pain, infection, and dentoalveolar abscesses. Early childhood caries (ECC) is defined as dental caries in children aged 6 years and younger and is a significant public health problem in South Africa. According to the Global Burden of Disease study, untreated dental caries of primary teeth affects 532 million children. Untreated dental caries has many detrimental effects which can affect the physical development and reduce the quality of life of affected children. Furthermore, long-term untreated dental caries can result in school absenteeism, low BMI, and poor educational outcomes.ObjectiveThe purpose of this study was to determine the prevalence and severity of ECC in South Africa in children under the age of 6 years.MethodsAll cross-sectional studies documenting the prevalence and severity of dental disease (decayed, missing, and filled teeth scores) will be included. Various databases will be searched for eligible studies. Only studies conducted on South African children aged 6 years and under will be included. There will be no restriction on the time or language of publication. The quality of all eligible studies will be analyzed by a risk of bias tool developed by the Joanna Briggs Institute. The results will be presented narratively, and if possible, a meta-analysis will be conducted.ResultsThe protocol is registered with PROSPERO. The literature search was initially conducted in November 2018 and was repeated in November 2020.ConclusionsThe results of this study will be used to advise stakeholders of the prevalence and severity of dental disease in children under 6 years of age in South Africa.Trial RegistrationPROSPERO CRD42018112161; International Registered Report Identifier (IRRID)DERR1-10.2196/25795