Severe sub-cortical white matter abnormalities are unusual features in Wilson's disease and are reported to be poorly or not responsive to copper chelating therapy or to be worsened by it. We report on a 12-year-old boy with Wilson's disease and extensive sub-cortical white matter involvement. After five years of copper chelating therapy, an appreciable improvement of these lesions was obtained. The physiopathology of these unusual cerebral white matter abnormalities is discussed.