En coup de sabre variant of linear morphea (LM) is a rare sclerotic skin disorder characterized by disfiguring linear depression of the frontal or frontoparietal forehead. Current attempts for cosmetic correction of atrophic lesions must be preceded by an evaluation of disease activity of LM, either by a sufficient clinical assessment or histologic evidence. Corrective procedures including corrective surgery, autologous fat grafting, hyaluronic acid filler injections were performed with varying degrees of success; still, there is a need for treatment options with non-invasive and long-term maintenance effects. Herein we report the use of micronized acellular dermal matrix filler as a novel and successful treatment for the atrophic defect of LM in a 24-year-old female. Molecular characteristics of the micronized acellular dermal matrix filler give enhanced durability and prolonged volume consistency, which results in a long-term extracellular matrix remodeling effect.