HIV infection predisposes patients to AIDS-defining malignancies, some of which, such as Kaposi's sarcoma and non-Hodgkin lymphoma, can affect the lungs. In 1996, AIDS-related mortality started to fall sharply in industrialized countries following the introduction of highly active antiretroviral treatments (HAART). This was accompanied by an increase in the proportion of deaths attributable to non AIDS-defining solid tumors, and especially lung cancer (LC). The increased risk of LC relative to the general population of the same age seems to be due partly to a higher prevalence of smoking among HIV-infected subjects. The average age of HIV-infected patients at LC diagnosis is about 45 years. Most patients are symptomatic at diagnosis and have only mild or moderate immunosuppression. LC is diagnosed when it is locally advanced or metastatic (stages III-IV) in 75-90% of cases, as in patients with unknown HIV serostatus. Adenocarcinoma is the most frequent histologic type. The prognosis of LC is poorer in HIV-infected patients than in the general population. Data on the efficacy and toxicity of chemotherapy in this setting are rare and rather imprecise. Surgery remains the reference treatment for localized disease in patients with adequate functional status and general health, regardless of their immune status. Prospective clinical trials are needed to define the optimal LC treatment strategies in HIV-infected patients.