BACKGROUND: Malaysia has an estimated hepatitis C virus (HCV) prevalence of 1.9% among its adult population and a history of providing HCV treatment in the public sector. In 2019, Malaysia launched a 5-year national strategic plan for viral hepatitis control and has been expanding HCV testing and treatment to the primary care and community levels, while actively engaging key populations in services for hepatitis care. The Ministry of Health (MoH) is seeking to specifically understand how to better target HCV services at men who have sex with men (MSM); HCV self-testing could increase the uptake of HCV testing among this group. METHODS: We aim to integrate HCV antibody self-testing into an existing online platform used for HIV self-testing, to evaluate the acceptability and impact of an online HCV self-testing programme in Malaysia. This is a non-blinded parallel group quasi-randomised superiority study comparing HCV self-testing via an online distribution model with the standard care, which involves attending a clinic for facility-based HCV antibody testing (control, 2:1). Participants will be randomised to either the HCV self-testing via online distribution arm, in which either an oral fluid- or blood-based HCV self-test kit will be mailed to them, or the control arm, where they will be provided with information about the nearest centre with HCV testing. The primary outcome is the number and proportion of participants who report completion of testing. Secondary outcomes include the number and proportion of participants who (a) receive a positive result and are made aware of their status, (b) are referred to and complete HCV RNA confirmatory testing, and (c) start treatment. Acceptability, feasibility, attitudes around HCV testing, and cost will also be evaluated. The target sample size is 750 participants. DISCUSSION: This study is one of the first in the world to explore the real-world impact of HCV self-testing on key populations using online platforms and compare this with standard HCV testing services. The outcomes of this study will provide critical evidence about testing uptake, linkage to care, acceptability, and any social harms that may emerge due to HCV self-testing. TRIAL REGISTRATION: ClinicalTrials.gov NCT04982718.