Background: Immune dysregulation is undoubtedly implicated in the pathogenesis of oral lichen planus (OLP) and considering the importance of miR-155 in the regulation of the immune response the present study is conducted to assess salivary levels of miR-155 in patients with oral lichen planus lesions and compare these levels before and after corticosteroid therapy to explore its possible implication in the pathogenesis OLP. Methods: Thirty patients were enrolled in this study, 15 healthy individuals with normal mucosa as controls and 15 patients diagnosed with atrophic/erosive OLP lesions. Patients were treated with topical corticosteroid. Salivary levels of miR-155 were assessed before and after 4 weeks of topical steroids therapy. Clinical improvement was assessed via VAS score and Thongprasom scale. Results: A significant reduction of miR-155 levels four weeks post treatment was recorded with a value of 55.67%. There was a highly significant direct correlation between miR-155 levels and VAS score. Conclusion: The overexpression of miR-155 in OLP patients before treatment with its obvious reduction four weeks after therapy suggests it could be directly involved in OLP pathogenesis and shedding a light on the potential of miR-155 to act as an innovative therapeutic target for OLP.