INTRODUCTION: Oral lichen planus is a common chronic inflammatory muco-cutaneous disease. Although the cause of oral lichen planus is not well known, T-lymphocyte infiltrate suggests a cell mediated immunological damage to basal cell layer of the epithelium. Its suggested treatment is topical corticosteroid. A promising new treatment for oral lichen planus [OLP] is the topical application of hyaluronic acid [HA], which has shown beneficial effect on wound healing. OBJECTIVES: to evaluate the effect of hyaluronic acid gel in the treatment of erosive oral lichen planus in comparison with topically applied corticosteroids. MATERIALS AND METHODS: a randomized, parallel, controlled clinical study was conducted on twenty patients who were randomly divided into two groups. Group I received topical application of corticosteroid (triamcinolone acetonide) 4-5 daily, for 28 days and Group II was similarly treated using hyaluronic acid 0.2% gel. Subjective symptom and Visual Analogue Scale (VAS) were recorded at base line, after 10 days and at 3 months. The objective sign clinical score was recorded at baseline, 1 and 3 months post –treatment. RESULTS: Both groups showed decrease in the lesion size and symptoms of OLP. The HA treated group showed a significantly higher decrease in the pain score in comparison to the corticosteroid treated group. Regarding the healing score, the corticosteroid group showed superior results than that shown with the HA. CONCLUSIONS: HA 0.2% gel is effective in the treatment of OLP, it resulted in a decrease in symptoms and signs of the disease. HA resulted in more control of pain when compared to topical corticosteroid.