The brain may be affected by a variety of abnormalities in association with human immunodeficiency virus (HIV) infection. Knowledge of their existence and characteristic imaging features are important to radiologists for detection, diagnosis, and initiation of an appropriate treatment. Although there is a considerable overlap in the imaging characteristics of different entities, some findings are found to be very suggestive of a particular disease. The CT and MR imaging techniques are commonly used in the diagnosis of neurological disorders in acquired immunodeficiency syndrome (AIDS) patients, to verify treatment response and to guide brain biopsy. This review attempts to describe CT and MR features of infectious and malignant brain disorders in HIV-seropositive patients.