Abstract Background: Psoriasis associated with human immunodeficiency virus (HIV) infection has been reported to be severe and perhaps associated with decreased survival. Objective: Our purpose was to document the natural history, response to therapy, and effect of psoriasis and its treatment on survival in HIV-infected patients with psoriasis. Methods: This was an observational cohort study of 50 persons with psoriasis and HIV infection followed up during a 2-year period. Results: In one third of the patients the psoriasis appeared before 1978, the year when HIV seroconversion began in San Francisco (group I). In two thirds psoriasis developed after 1978 (group II). Group I had a lower mean age of onset (19 vs 36 years) and more commonly had a family history of psoriasis. Palmoplantar and inverse psoriasis were more common in group II. Severe psoriasis occurred in one fourth of this group (12 of 50 patients). The median survival in this group after diagnosis of acquired immunodeficiency syndrome (AIDS) was 19 months, which is comparable to the median survival for all AIDS patients diagnosed in San Francisco between 1984 and 1990. Conclusion: Psoriasis in the setting of HIV disease may be mild, moderate, or severe. Standard therapies and zidovudine are effective in management. Survival does not seem to be adversely affected by the presence of psoriasis or its therapy.