Background: Oral lichen planus (OLP) is a chronic autoimmune disease that frequently affects the oral mucosa. Patients with OLP tend to present with plaque accumulation which may further exacerbate the lichenoid lesion, thus plaque control may improve the quality of life of patients. The aim of this review was to test the effect of plaque control on OLP with gingival manifestations. Methods: Systematic review following the PRISMA checklist. A search was conducted through Medline, Embase and the Cochrane Library Database up to March 2020 and complemented by a manual search in some relevant journals. Randomised Controlled Trials (RCTs) reporting plaque interventions and their effects in populations with gingival manifestations of OLP, with a follow-up period of at least 3 months were included. Risk of Bias was assessed using the Cochrane Collaboration Tool in Randomised Trials. Results: The initial search generated 89 sources, resulting in final inclusion of three RCTs following full-text reading. The control groups were asked to continue their regular oral hygiene routine, while test groups received additional tailored oral hygiene advice as the intervention. Two of the included papers had sufficiently similar design to be included in meta-analysis. The oral hygiene intervention was associated with improvements in clinical disease status (Escudier index) and patient-reported outcomes (OHIP-14) from baseline compared with the control group. Differences in visual analogue scores for pain between groups were not statistically different between test and control groups. Two studies were judged to have low risk of bias, while one (not included in meta-analysis) had high risk of bias. Conclusion: Improvements in disease and patient-reported outcomes can occur as a result of oral hygiene instruction in patients with gingival manifestations of OLP. Keywords: Oral lichen planus, gingival involvement, plaque control.