The paper describes a rare case of rapidly progressive generalized pneumocystosis in HIV infection in a 43-year-old patient who died 4.5-5 months after disease onset. The specific feature of the case is that in pneumocystosis there was multiple organ dysfunction, as well as infiltrate decay to form small and large lung cavities similar to tuberculosis ones. Autopsy disclosed Pneumocystis-induced changes in the liver, spleen, lymph nodes, and the wall of the ileum. Pneumocystosis and HIV infection were diagnosed only posthumously. The specificity of organ diseases was immunohistochemically verified.