Background: Removable orthodontic treatment corrects dental and skeletal malocclusion by utilising various types of removable appliances. Although removable orthodontic treatment has a reduced risk of dental caries compared to fixed orthodontic treatment, removable appliances create niches for cariogenic microorganisms to increase their numbers and lead to an ecological shift. However, there is insufficient information on caries prevention during removable orthodontic treatment. The protocol details the research for a scoping review of caries prevention during removable orthodontic treatment. Methods: This scoping review will be conducted according to the Preferred Reporting Items for Systemic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) and Joanna Briggs Institute (JBI) Manual for Evidence Synthesis guidelines. Published primary and secondary research studies (including reviews), guidelines, websites, and reports that are written in English until April 2022 will be searched from seven databases, including Dentistry and Oral Sciences Source, CINAHL, MEDLINE, via EBSCOHost, Scopus, Cochrane, Google, and Google Scholar. Two reviewers (HP and ZM) will analyse the retrieved articles simultaneously using the parameters and three-step strategy recommended by JBI. Obtained numbers of included and excluded identified sources will be presented in a PRISMA flow diagram and the data extraction table will demonstrate the variables from included sources. Conclusions: The findings of this review will be summarised in a narrative description to facilitate guidance in clinical practice and research for health professionals.