This clinical report describes the treatment of a patient in need of an immediate complete denture who presented with severe erosive lichen planus. In conjunction with an immediate complete denture, tacrolimus (0.1%) ointment, an immunosuppressive agent, was applied topically over the lesions. There was a significant reduction in the size of the lesions at the second week of treatment, allowing the patient to tolerate the prosthesis without pain, thereby improving her quality of life.