The CT and/or MR findings were reviewed in 43 patients with head and neck disease; 27 had AIDS, 14 had AIDS-related complex, and two had positive human immunodeficiency virus serologies. Fourteen patients had infections, 15 had tumors, and 15 had benign lymphoid hyperplasia. Deep cervical infections were caused by bacterial and mycobacterial organisms, including Mycobacterium avium-intracellulare. Bacterial infections were clinically more virulent than they would be in immunocompetent patients. Neoplasms included Kaposi sarcoma, lymphoma, and squamous cell carcinoma. Benign lymphoid hyperplasia demonstrated enlargement of the cervical lymph nodes, adenoids, and tonsils. Although there was considerable overlap in the imaging characteristics of the various diseases seen, several distinguishing features were noted. Cellulitis, with infiltration and thickening of the subcutaneous fat, was typical of bacterial infections, but was uncommon with tumors or mycobacterial infections. Lymph nodes with necrotic centers were seen with Kaposi sarcoma, squamous cell carcinoma, and mycobacterial infection, but not with lymphoma or benign lymphoid hyperplasia. Benign adenoidal enlargement is usually symmetric with a flat anterior border, but bulky lesions indistinguishable from tumor were seen in two patients. It is important for radiologists to be aware of the spectrum of head and neck disease in patients with human immunodeficiency virus. The CT and MR assessment can guide biopsy and assist in planning therapy.