Oral lichen planus is a common chronic mucocutaneous disease with various clinical forms. Erosive-ulcerative forms usually cause symptoms of pain and discomfort. The most important complication of OLP is development of oral squamous cell carcinoma, although this is a very controversial matter. various treatments have been suggested for OLP but their results are unsatisfactory. Through the experiences of the investigators, corticosteroids (in any form)is not a wise option for treating OLP and has many side effects . More over, immunosuppressive therapy did not influence the risk for oral cancer. The purpose of the study is to determine the efficacy of free soft tissue graft in the treatment of precancerous and symptomatic lesions of OLP. Removal of the lesions up to submucosa has been done. The graft sliced from healthy mucosa also up to submucosa. Then graft will be sutured in position.