Extraskeletal Ewing's sarcoma is often described as a tumour involving the soft tissues of the lower extremities and the paravertebral region. Involvement of the paranasal sinus is a very rare entity. We present a case of primary Ewing's sarcoma of the paranasal sinus extending into the middle cranial fossa in a 40-year-old female. CT and MRI findings of this unusual case are discussed. To our knowledge, this case is the first to be reported with CT and MRI documentation.