Although patients infected with human immunodeficiency virus (HIV) might be expected to have more severe illness due to influenza virus infection than normal persons, the course of influenza in such patients has not been well delineated. We describe six consecutive HIV-infected patients at San Francisco General Hospital in whom influenza virus was isolated from induced sputum or bronchoalveolar lavage specimens between December 1988 and March 1989. Although neither clinical presentation of influenza nor rate of secondary complications appeared to be altered from that in healthy individuals, our power of comparison was limited by small sample size. However, a high prevalence of hypoxemia and a trend toward prolonged duration of illness were identified. Larger, controlled studies are needed to define the course of influenza virus infection in HIV-infected patients as compared with nonimmunosuppressed patients.