Ataxia Telangiectasia (AT) is an autosomal recessive inherited disorder in which cutaneous and scleral Telangiectasia, cerebellar ataxia and immunodeficiency occur. There is a high incidence of development of malignant tumors, mainly lymphomas. Cerebellar atrophy is the most prominent abnormality and is shown better by magnetic resonance imaging (MRI) than CT-Scan. Intracranial hemorrhage occurs rarely. We report a 7 years old boy who admitted for recurrent pulmonary infections. His examination showed ataxic gait with decreased deep tendon reflexes in lower extremities. He had telangiectasia in the eyes and his speech was slurred and difficult. Brain MRI showed cerebellar atrophy with diffuse hyperintensity in white matter, most prominent in occipital region, which was suggestive of leukodystrophy. This white matter change was not reported before in AT.