Lentigo maligna is the in situ phase of lentigo maligna melanoma, and if left untreated it may progress to invasive melanoma. It most commonly occurs on the exposed sites of the face and neck of middle-aged or elderly patients. Conventional surgery using a 5-10 mm margin is the recommended treatment; however, lesions can be quite large and surgical removal may involve extensive plastic repair. We report an elderly patient with a large lentigo maligna on the scalp who was reluctant to have surgery. We tried topical imiquimod 5% cream (Aldara), a local immunomodulator, which has recently become available for the treatment of external genital and perianal warts. Initially used over a test area and then over the whole of the lesion, for a total of 7 months, the imiquimod cream resulted in complete clinical and histological cure. The patient has been followed up for 9 months without evidence of recurrence.