Association of lichen planus and cutaneous malignancies is rare. Reports of neoplastic changes are mostly related to buccal chronic erosive lichen planus. We report herein a 29-year-old man who developed squamous cell carcinoma on previous lesions of chronic hypertrophic lichen planus of lower legs. Careful follow up of patients with chronic lichen planus and biopsy sampling of uncommon lesions is required to rule out malignant transformation.